Re: [algogeeks] Maximum size square sub-matrix with all 1s
@ atul and saurabh Here is my code of what m trying to implement . here starting at bottom right corner we try to come up moving row by row . in end b matrix contain's dimention of rectangle which can be formed from Aij in Bij (width,height) plz.. post what u make of it... can it be improved to work for all case's ?? #includeiostream #includeconio.h using namespace std; main() { int width=0,height=1; int a[6][6]={0,1,1,1,1,0, 0,0,0,1,1,0, 0,1,1,1,1,0, 0,1,1,0,0,0, 0,1,1,0,0,0, 0,0,0,0,0,0 }; int b[6][6][2]={0}; int i,j; for(i=0;i6;i++) { b[5][i][width]=1; b[i][5][width]=1; b[5][i][height]=1; b[i][5][height]=1; } for(i=4;i=0;i--) { for(j=4;j=0;j--) { if(a[i][j]!=a[i+1][j] a[i][j]!=a[i][j+1]) { b[i][j][width]=1; b[i][j][height]=1; } else if(a[i][j]==a[i][j+1] a[i][j]!=a[i+1][j]) { b[i][j][width]=b[i][j+1][width]+1; b[i][j][height]=1; //printf(widht\n); } else if(a[i][j]==a[i+1][j] a[i][j]!=a[i][j+1]) { b[i][j][width]=1; b[i][j][height]=b[i+1][j][height]+1; // printf(height\n); } else { b[i][j][width]=min(b[i+1][j][width],b[i][j+1][width]+1); b[i][j][height]=min(b[i+1][j][height]+1,b[i][j+1][height]); } } } for(i=0;i6;i++) { for(j=0;j6;j++) { printf(%d,%d ,b[i][j][width],b[i][j][height]); } printf(\n); } getch(); } On Wed, Mar 14, 2012 at 8:59 PM, atul anand atul.87fri...@gmail.com wrote: @Sourabh : here we are talking abt 2 different problems in this post..which are little bit similar. 1) original question says find max subset of matix contaning '1' and '0' we knw recurrence to solve this problem , as posted above. 2) now your question is to find max subset of matrix which contain +ve or -ve numbers , not necessarily only '1' or '0' so in my solution , you need to give some input to solve this problem and that input is say matrix m[][]. if you check my solution then in just modifies input matrix to find solution , its space complexity is O(1). On Thu, Mar 15, 2012 at 12:26 AM, Sourabh Singh singhsourab...@gmail.comwrote: @atul 1) it won't work for large dimention's coz their is a limit to size of array we can declare on stack. ( which is typically 10^6 as far as i know :-) ). 2) the algo i m trying to find would work in linear time. while this one is more then O(n^2) fo rvery very large input this algo would be very very slow.. making it impractial.. ( it's like if u can find substring's in linear time then why use an O(n^2) algo ;-) ) NOTE: sry if m getting any fact's wrong m in mid of exam's (so a bit short on time to check implemention of your algo right now ) On Wed, Mar 14, 2012 at 9:07 AM, atul anand atul.87fri...@gmail.comwrote: @rahul: i have alreday explained it in the provided link. @sourbh : why it would not work for large dimension On 14 Mar 2012 19:39, rahul sharma rahul23111...@gmail.com wrote: @atul..plz tell me an example for square matrix...actually i faced it first tym...it executes...but explain plz.. On Wed, Mar 14, 2012 at 6:56 PM, Sourabh Singh singhsourab...@gmail.com wrote: @atul Also the histogram algo and algo given by you can't work on very very big dimentions. say 10^5 x 10^5 matrix. but if we can find a DP then we just need to keep 2 row's at a time. :-) On Tue, Mar 13, 2012 at 1:03 PM, Sourabh Singh singhsourab...@gmail.com wrote: @atul read it .. it's good but more or less like the histogram algo.. i wanted a DP. approach.. here is some of wat i heard from a senior in colg.. 1. at every index we can keep 4 variable ht: height of max rectangle possible at index above current wt width hl:height of max rectangle possible at index left of current wl: now problem is which one to take for current... index On Tue, Mar 13, 2012 at 10:52 AM, atul anand
Re: [algogeeks] Maximum size square sub-matrix with all 1s
@atul Also the histogram algo and algo given by you can't work on very very big dimentions. say 10^5 x 10^5 matrix. but if we can find a DP then we just need to keep 2 row's at a time. :-) On Tue, Mar 13, 2012 at 1:03 PM, Sourabh Singh singhsourab...@gmail.comwrote: @atul read it .. it's good but more or less like the histogram algo.. i wanted a DP. approach.. here is some of wat i heard from a senior in colg.. 1. at every index we can keep 4 variable ht: height of max rectangle possible at index above current wt width hl:height of max rectangle possible at index left of current wl: now problem is which one to take for current... index On Tue, Mar 13, 2012 at 10:52 AM, atul anand atul.87fri...@gmail.comwrote: @ Sourabh: check solution i have posted in below link http://groups.google.com/group/algogeeks/browse_thread/thread/91a17f7c78c2319e/991d1c2625a62ff0?hl=enlnk=gstq=rectangle+of+max+sum+MS+Q#991d1c2625a62ff0 On Tue, Mar 13, 2012 at 10:26 PM, Sourabh Singh singhsourab...@gmail.com wrote: @ ALL finding square matrix is quite a standard question and nw an easy one as everyone knows the reccussence atul has given. but i wanted to find max rectangle.. i know there is a DP for it. in O(n^2). for nxn matrix..don't know the whole approach .but here is what i remember.. 1. aproach is simple to keep track of max rectangle which can be formed from any point taking that point as top left corner of max rectangle and proceed further down . can someone suggest how can be proceed further.. [ NOTE: problem occurs mainly when their are more than one rectangles which can be formed from same point ] plz.. don't suggest the histogram method it's just a dirty way of avoiding to work on getting this DP right. :-) On Mon, Mar 12, 2012 at 11:29 PM, atul anand atul.87fri...@gmail.comwrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.com wrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
Re: [algogeeks] Maximum size square sub-matrix with all 1s
@atul..plz tell me an example for square matrix...actually i faced it first tym...it executes...but explain plz.. On Wed, Mar 14, 2012 at 6:56 PM, Sourabh Singh singhsourab...@gmail.comwrote: @atul Also the histogram algo and algo given by you can't work on very very big dimentions. say 10^5 x 10^5 matrix. but if we can find a DP then we just need to keep 2 row's at a time. :-) On Tue, Mar 13, 2012 at 1:03 PM, Sourabh Singh singhsourab...@gmail.comwrote: @atul read it .. it's good but more or less like the histogram algo.. i wanted a DP. approach.. here is some of wat i heard from a senior in colg.. 1. at every index we can keep 4 variable ht: height of max rectangle possible at index above current wt width hl:height of max rectangle possible at index left of current wl: now problem is which one to take for current... index On Tue, Mar 13, 2012 at 10:52 AM, atul anand atul.87fri...@gmail.comwrote: @ Sourabh: check solution i have posted in below link http://groups.google.com/group/algogeeks/browse_thread/thread/91a17f7c78c2319e/991d1c2625a62ff0?hl=enlnk=gstq=rectangle+of+max+sum+MS+Q#991d1c2625a62ff0 On Tue, Mar 13, 2012 at 10:26 PM, Sourabh Singh singhsourab...@gmail.com wrote: @ ALL finding square matrix is quite a standard question and nw an easy one as everyone knows the reccussence atul has given. but i wanted to find max rectangle.. i know there is a DP for it. in O(n^2). for nxn matrix..don't know the whole approach .but here is what i remember.. 1. aproach is simple to keep track of max rectangle which can be formed from any point taking that point as top left corner of max rectangle and proceed further down . can someone suggest how can be proceed further.. [ NOTE: problem occurs mainly when their are more than one rectangles which can be formed from same point ] plz.. don't suggest the histogram method it's just a dirty way of avoiding to work on getting this DP right. :-) On Mon, Mar 12, 2012 at 11:29 PM, atul anand atul.87fri...@gmail.comwrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.com wrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
Re: [algogeeks] Maximum size square sub-matrix with all 1s
@rahul: i have alreday explained it in the provided link. @sourbh : why it would not work for large dimension On 14 Mar 2012 19:39, rahul sharma rahul23111...@gmail.com wrote: @atul..plz tell me an example for square matrix...actually i faced it first tym...it executes...but explain plz.. On Wed, Mar 14, 2012 at 6:56 PM, Sourabh Singh singhsourab...@gmail.comwrote: @atul Also the histogram algo and algo given by you can't work on very very big dimentions. say 10^5 x 10^5 matrix. but if we can find a DP then we just need to keep 2 row's at a time. :-) On Tue, Mar 13, 2012 at 1:03 PM, Sourabh Singh singhsourab...@gmail.comwrote: @atul read it .. it's good but more or less like the histogram algo.. i wanted a DP. approach.. here is some of wat i heard from a senior in colg.. 1. at every index we can keep 4 variable ht: height of max rectangle possible at index above current wt width hl:height of max rectangle possible at index left of current wl: now problem is which one to take for current... index On Tue, Mar 13, 2012 at 10:52 AM, atul anand atul.87fri...@gmail.comwrote: @ Sourabh: check solution i have posted in below link http://groups.google.com/group/algogeeks/browse_thread/thread/91a17f7c78c2319e/991d1c2625a62ff0?hl=enlnk=gstq=rectangle+of+max+sum+MS+Q#991d1c2625a62ff0 On Tue, Mar 13, 2012 at 10:26 PM, Sourabh Singh singhsourab...@gmail.com wrote: @ ALL finding square matrix is quite a standard question and nw an easy one as everyone knows the reccussence atul has given. but i wanted to find max rectangle.. i know there is a DP for it. in O(n^2). for nxn matrix..don't know the whole approach .but here is what i remember.. 1. aproach is simple to keep track of max rectangle which can be formed from any point taking that point as top left corner of max rectangle and proceed further down . can someone suggest how can be proceed further.. [ NOTE: problem occurs mainly when their are more than one rectangles which can be formed from same point ] plz.. don't suggest the histogram method it's just a dirty way of avoiding to work on getting this DP right. :-) On Mon, Mar 12, 2012 at 11:29 PM, atul anand atul.87fri...@gmail.comwrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.com wrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at
Re: [algogeeks] Maximum size square sub-matrix with all 1s
@atul 1) it won't work for large dimention's coz their is a limit to size of array we can declare on stack. ( which is typically 10^6 as far as i know :-) ). 2) the algo i m trying to find would work in linear time. while this one is more then O(n^2) fo rvery very large input this algo would be very very slow.. making it impractial.. ( it's like if u can find substring's in linear time then why use an O(n^2) algo ;-) ) NOTE: sry if m getting any fact's wrong m in mid of exam's (so a bit short on time to check implemention of your algo right now ) On Wed, Mar 14, 2012 at 9:07 AM, atul anand atul.87fri...@gmail.com wrote: @rahul: i have alreday explained it in the provided link. @sourbh : why it would not work for large dimension On 14 Mar 2012 19:39, rahul sharma rahul23111...@gmail.com wrote: @atul..plz tell me an example for square matrix...actually i faced it first tym...it executes...but explain plz.. On Wed, Mar 14, 2012 at 6:56 PM, Sourabh Singh singhsourab...@gmail.comwrote: @atul Also the histogram algo and algo given by you can't work on very very big dimentions. say 10^5 x 10^5 matrix. but if we can find a DP then we just need to keep 2 row's at a time. :-) On Tue, Mar 13, 2012 at 1:03 PM, Sourabh Singh singhsourab...@gmail.com wrote: @atul read it .. it's good but more or less like the histogram algo.. i wanted a DP. approach.. here is some of wat i heard from a senior in colg.. 1. at every index we can keep 4 variable ht: height of max rectangle possible at index above current wt width hl:height of max rectangle possible at index left of current wl: now problem is which one to take for current... index On Tue, Mar 13, 2012 at 10:52 AM, atul anand atul.87fri...@gmail.comwrote: @ Sourabh: check solution i have posted in below link http://groups.google.com/group/algogeeks/browse_thread/thread/91a17f7c78c2319e/991d1c2625a62ff0?hl=enlnk=gstq=rectangle+of+max+sum+MS+Q#991d1c2625a62ff0 On Tue, Mar 13, 2012 at 10:26 PM, Sourabh Singh singhsourab...@gmail.com wrote: @ ALL finding square matrix is quite a standard question and nw an easy one as everyone knows the reccussence atul has given. but i wanted to find max rectangle.. i know there is a DP for it. in O(n^2). for nxn matrix..don't know the whole approach .but here is what i remember.. 1. aproach is simple to keep track of max rectangle which can be formed from any point taking that point as top left corner of max rectangle and proceed further down . can someone suggest how can be proceed further.. [ NOTE: problem occurs mainly when their are more than one rectangles which can be formed from same point ] plz.. don't suggest the histogram method it's just a dirty way of avoiding to work on getting this DP right. :-) On Mon, Mar 12, 2012 at 11:29 PM, atul anand atul.87fri...@gmail.com wrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.com wrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You
Re: [algogeeks] Maximum size square sub-matrix with all 1s
@rahul may be this will help you.. /* Given a binary matrix, find out the maximum size square sub-matrix with all 1s. 1. O(n^3) sol is very obvious 2. O(n^2) sol [ this file] 3. O(n) sol [ possible but we need to know tucker matrix, etc advanced set theory's] */ #includeiostream #includeconio.h int b[6][6]; using namespace std; main() { int i,j,t; int a[6][6]= { 0,0,0,1,0,1, 0,1,1,1,0,0, 1,1,1,1,0,1, 0,1,1,1,1,0, 1,0,0,1,0,0, 0,1,0,1,1,0,}; for(i=0;i6;i++) for(j=0;j6;j++) { if(a[i][j]==1) { b[i][j]=min(min(b[i-1][j],b[i][j-1]),b[j-1][i-1])+1; } else b[i][j]=0; } for(i=0;i6;i++) { for(j=0;j6;j++) {printf( %d,a[i][j]); } printf(\n); } printf(\n\n\n\n\n); for(i=0;i6;i++) { for(j=0;j6;j++) {printf( %d,b[i][j]); } printf(\n); } getch(); return 0; } On Wed, Mar 14, 2012 at 11:56 AM, Sourabh Singh singhsourab...@gmail.comwrote: @atul 1) it won't work for large dimention's coz their is a limit to size of array we can declare on stack. ( which is typically 10^6 as far as i know :-) ). 2) the algo i m trying to find would work in linear time. while this one is more then O(n^2) fo rvery very large input this algo would be very very slow.. making it impractial.. ( it's like if u can find substring's in linear time then why use an O(n^2) algo ;-) ) NOTE: sry if m getting any fact's wrong m in mid of exam's (so a bit short on time to check implemention of your algo right now ) On Wed, Mar 14, 2012 at 9:07 AM, atul anand atul.87fri...@gmail.comwrote: @rahul: i have alreday explained it in the provided link. @sourbh : why it would not work for large dimension On 14 Mar 2012 19:39, rahul sharma rahul23111...@gmail.com wrote: @atul..plz tell me an example for square matrix...actually i faced it first tym...it executes...but explain plz.. On Wed, Mar 14, 2012 at 6:56 PM, Sourabh Singh singhsourab...@gmail.com wrote: @atul Also the histogram algo and algo given by you can't work on very very big dimentions. say 10^5 x 10^5 matrix. but if we can find a DP then we just need to keep 2 row's at a time. :-) On Tue, Mar 13, 2012 at 1:03 PM, Sourabh Singh singhsourab...@gmail.com wrote: @atul read it .. it's good but more or less like the histogram algo.. i wanted a DP. approach.. here is some of wat i heard from a senior in colg.. 1. at every index we can keep 4 variable ht: height of max rectangle possible at index above current wt width hl:height of max rectangle possible at index left of current wl: now problem is which one to take for current... index On Tue, Mar 13, 2012 at 10:52 AM, atul anand atul.87fri...@gmail.comwrote: @ Sourabh: check solution i have posted in below link http://groups.google.com/group/algogeeks/browse_thread/thread/91a17f7c78c2319e/991d1c2625a62ff0?hl=enlnk=gstq=rectangle+of+max+sum+MS+Q#991d1c2625a62ff0 On Tue, Mar 13, 2012 at 10:26 PM, Sourabh Singh singhsourab...@gmail.com wrote: @ ALL finding square matrix is quite a standard question and nw an easy one as everyone knows the reccussence atul has given. but i wanted to find max rectangle.. i know there is a DP for it. in O(n^2). for nxn matrix..don't know the whole approach .but here is what i remember.. 1. aproach is simple to keep track of max rectangle which can be formed from any point taking that point as top left corner of max rectangle and proceed further down . can someone suggest how can be proceed further.. [ NOTE: problem occurs mainly when their are more than one rectangles which can be formed from same point ] plz.. don't suggest the histogram method it's just a dirty way of avoiding to work on getting this DP right. :-) On Mon, Mar 12, 2012 at 11:29 PM, atul anand atul.87fri...@gmail.com wrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.com wrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com.
Re: [algogeeks] Maximum size square sub-matrix with all 1s
On 3/15/12, Sourabh Singh singhsourab...@gmail.com wrote: @rahul may be this will help you.. /* Given a binary matrix, find out the maximum size square sub-matrix with all 1s. 1. O(n^3) sol is very obvious 2. O(n^2) sol [ this file] 3. O(n) sol [ possible but we need to know tucker matrix, etc advanced set theory's] */ #includeiostream #includeconio.h int b[6][6]; using namespace std; main() { int i,j,t; int a[6][6]= { 0,0,0,1,0,1, 0,1,1,1,0,0, 1,1,1,1,0,1, 0,1,1,1,1,0, 1,0,0,1,0,0, 0,1,0,1,1,0,}; for(i=0;i6;i++) for(j=0;j6;j++) { if(a[i][j]==1) { b[i][j]=min(min(b[i-1][j],b[i][j-1]),b[j-1][i-1])+1; } else b[i][j]=0; } for(i=0;i6;i++) { for(j=0;j6;j++) {printf( %d,a[i][j]); } printf(\n); } printf(\n\n\n\n\n); for(i=0;i6;i++) { for(j=0;j6;j++) {printf( %d,b[i][j]); } printf(\n); } getch(); return 0; } On Wed, Mar 14, 2012 at 11:56 AM, Sourabh Singh singhsourab...@gmail.comwrote: @atul 1) it won't work for large dimention's coz their is a limit to size of array we can declare on stack. ( which is typically 10^6 as far as i know :-) ). 2) the algo i m trying to find would work in linear time. while this one is more then O(n^2) fo rvery very large input this algo would be very very slow.. making it impractial.. ( it's like if u can find substring's in linear time then why use an O(n^2) algo ;-) ) NOTE: sry if m getting any fact's wrong m in mid of exam's (so a bit short on time to check implemention of your algo right now ) On Wed, Mar 14, 2012 at 9:07 AM, atul anand atul.87fri...@gmail.comwrote: @rahul: i have alreday explained it in the provided link. @sourbh : why it would not work for large dimension On 14 Mar 2012 19:39, rahul sharma rahul23111...@gmail.com wrote: @atul..plz tell me an example for square matrix...actually i faced it first tym...it executes...but explain plz.. On Wed, Mar 14, 2012 at 6:56 PM, Sourabh Singh singhsourab...@gmail.com wrote: @atul Also the histogram algo and algo given by you can't work on very very big dimentions. say 10^5 x 10^5 matrix. but if we can find a DP then we just need to keep 2 row's at a time. :-) On Tue, Mar 13, 2012 at 1:03 PM, Sourabh Singh singhsourab...@gmail.com wrote: @atul read it .. it's good but more or less like the histogram algo.. i wanted a DP. approach.. here is some of wat i heard from a senior in colg.. 1. at every index we can keep 4 variable ht: height of max rectangle possible at index above current wt width hl:height of max rectangle possible at index left of current wl: now problem is which one to take for current... index On Tue, Mar 13, 2012 at 10:52 AM, atul anand atul.87fri...@gmail.comwrote: @ Sourabh: check solution i have posted in below link http://groups.google.com/group/algogeeks/browse_thread/thread/91a17f7c78c2319e/991d1c2625a62ff0?hl=enlnk=gstq=rectangle+of+max+sum+MS+Q#991d1c2625a62ff0 On Tue, Mar 13, 2012 at 10:26 PM, Sourabh Singh singhsourab...@gmail.com wrote: @ ALL finding square matrix is quite a standard question and nw an easy one as everyone knows the reccussence atul has given. but i wanted to find max rectangle.. i know there is a DP for it. in O(n^2). for nxn matrix..don't know the whole approach .but here is what i remember.. 1. aproach is simple to keep track of max rectangle which can be formed from any point taking that point as top left corner of max rectangle and proceed further down . can someone suggest how can be proceed further.. [ NOTE: problem occurs mainly when their are more than one rectangles which can be formed from same point ] plz.. don't suggest the histogram method it's just a dirty way of avoiding to work on getting this DP right. :-) On Mon, Mar 12, 2012 at 11:29 PM, atul anand atul.87fri...@gmail.com wrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.com wrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to
Re: [algogeeks] Maximum size square sub-matrix with all 1s
@sourabhThere are O(n^2) elements in the matrix of size nXn. Yes we can find patterns in a substring with n elements in O(n) but can you do that in O(sqrt(n)) (To complete your analogy), Beside's can you allocate a 10^6X10^6 matrix in an array? On 3/15/12, saurabh singh saurab...@gmail.com wrote: On 3/15/12, Sourabh Singh singhsourab...@gmail.com wrote: @rahul may be this will help you.. /* Given a binary matrix, find out the maximum size square sub-matrix with all 1s. 1. O(n^3) sol is very obvious 2. O(n^2) sol [ this file] 3. O(n) sol [ possible but we need to know tucker matrix, etc advanced set theory's] */ #includeiostream #includeconio.h int b[6][6]; using namespace std; main() { int i,j,t; int a[6][6]= { 0,0,0,1,0,1, 0,1,1,1,0,0, 1,1,1,1,0,1, 0,1,1,1,1,0, 1,0,0,1,0,0, 0,1,0,1,1,0,}; for(i=0;i6;i++) for(j=0;j6;j++) { if(a[i][j]==1) { b[i][j]=min(min(b[i-1][j],b[i][j-1]),b[j-1][i-1])+1; } else b[i][j]=0; } for(i=0;i6;i++) { for(j=0;j6;j++) {printf( %d,a[i][j]); } printf(\n); } printf(\n\n\n\n\n); for(i=0;i6;i++) { for(j=0;j6;j++) {printf( %d,b[i][j]); } printf(\n); } getch(); return 0; } On Wed, Mar 14, 2012 at 11:56 AM, Sourabh Singh singhsourab...@gmail.comwrote: @atul 1) it won't work for large dimention's coz their is a limit to size of array we can declare on stack. ( which is typically 10^6 as far as i know :-) ). 2) the algo i m trying to find would work in linear time. while this one is more then O(n^2) fo rvery very large input this algo would be very very slow.. making it impractial.. ( it's like if u can find substring's in linear time then why use an O(n^2) algo ;-) ) NOTE: sry if m getting any fact's wrong m in mid of exam's (so a bit short on time to check implemention of your algo right now ) On Wed, Mar 14, 2012 at 9:07 AM, atul anand atul.87fri...@gmail.comwrote: @rahul: i have alreday explained it in the provided link. @sourbh : why it would not work for large dimension On 14 Mar 2012 19:39, rahul sharma rahul23111...@gmail.com wrote: @atul..plz tell me an example for square matrix...actually i faced it first tym...it executes...but explain plz.. On Wed, Mar 14, 2012 at 6:56 PM, Sourabh Singh singhsourab...@gmail.com wrote: @atul Also the histogram algo and algo given by you can't work on very very big dimentions. say 10^5 x 10^5 matrix. but if we can find a DP then we just need to keep 2 row's at a time. :-) On Tue, Mar 13, 2012 at 1:03 PM, Sourabh Singh singhsourab...@gmail.com wrote: @atul read it .. it's good but more or less like the histogram algo.. i wanted a DP. approach.. here is some of wat i heard from a senior in colg.. 1. at every index we can keep 4 variable ht: height of max rectangle possible at index above current wt width hl:height of max rectangle possible at index left of current wl: now problem is which one to take for current... index On Tue, Mar 13, 2012 at 10:52 AM, atul anand atul.87fri...@gmail.comwrote: @ Sourabh: check solution i have posted in below link http://groups.google.com/group/algogeeks/browse_thread/thread/91a17f7c78c2319e/991d1c2625a62ff0?hl=enlnk=gstq=rectangle+of+max+sum+MS+Q#991d1c2625a62ff0 On Tue, Mar 13, 2012 at 10:26 PM, Sourabh Singh singhsourab...@gmail.com wrote: @ ALL finding square matrix is quite a standard question and nw an easy one as everyone knows the reccussence atul has given. but i wanted to find max rectangle.. i know there is a DP for it. in O(n^2). for nxn matrix..don't know the whole approach .but here is what i remember.. 1. aproach is simple to keep track of max rectangle which can be formed from any point taking that point as top left corner of max rectangle and proceed further down . can someone suggest how can be proceed further.. [ NOTE: problem occurs mainly when their are more than one rectangles which can be formed from same point ] plz.. don't suggest the histogram method it's just a dirty way of avoiding to work on getting this DP right. :-) On Mon, Mar 12, 2012 at 11:29 PM, atul anand atul.87fri...@gmail.com wrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.com wrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s.
Re: [algogeeks] Maximum size square sub-matrix with all 1s
@Sourabh : here we are talking abt 2 different problems in this post..which are little bit similar. 1) original question says find max subset of matix contaning '1' and '0' we knw recurrence to solve this problem , as posted above. 2) now your question is to find max subset of matrix which contain +ve or -ve numbers , not necessarily only '1' or '0' so in my solution , you need to give some input to solve this problem and that input is say matrix m[][]. if you check my solution then in just modifies input matrix to find solution , its space complexity is O(1). On Thu, Mar 15, 2012 at 12:26 AM, Sourabh Singh singhsourab...@gmail.comwrote: @atul 1) it won't work for large dimention's coz their is a limit to size of array we can declare on stack. ( which is typically 10^6 as far as i know :-) ). 2) the algo i m trying to find would work in linear time. while this one is more then O(n^2) fo rvery very large input this algo would be very very slow.. making it impractial.. ( it's like if u can find substring's in linear time then why use an O(n^2) algo ;-) ) NOTE: sry if m getting any fact's wrong m in mid of exam's (so a bit short on time to check implemention of your algo right now ) On Wed, Mar 14, 2012 at 9:07 AM, atul anand atul.87fri...@gmail.comwrote: @rahul: i have alreday explained it in the provided link. @sourbh : why it would not work for large dimension On 14 Mar 2012 19:39, rahul sharma rahul23111...@gmail.com wrote: @atul..plz tell me an example for square matrix...actually i faced it first tym...it executes...but explain plz.. On Wed, Mar 14, 2012 at 6:56 PM, Sourabh Singh singhsourab...@gmail.com wrote: @atul Also the histogram algo and algo given by you can't work on very very big dimentions. say 10^5 x 10^5 matrix. but if we can find a DP then we just need to keep 2 row's at a time. :-) On Tue, Mar 13, 2012 at 1:03 PM, Sourabh Singh singhsourab...@gmail.com wrote: @atul read it .. it's good but more or less like the histogram algo.. i wanted a DP. approach.. here is some of wat i heard from a senior in colg.. 1. at every index we can keep 4 variable ht: height of max rectangle possible at index above current wt width hl:height of max rectangle possible at index left of current wl: now problem is which one to take for current... index On Tue, Mar 13, 2012 at 10:52 AM, atul anand atul.87fri...@gmail.comwrote: @ Sourabh: check solution i have posted in below link http://groups.google.com/group/algogeeks/browse_thread/thread/91a17f7c78c2319e/991d1c2625a62ff0?hl=enlnk=gstq=rectangle+of+max+sum+MS+Q#991d1c2625a62ff0 On Tue, Mar 13, 2012 at 10:26 PM, Sourabh Singh singhsourab...@gmail.com wrote: @ ALL finding square matrix is quite a standard question and nw an easy one as everyone knows the reccussence atul has given. but i wanted to find max rectangle.. i know there is a DP for it. in O(n^2). for nxn matrix..don't know the whole approach .but here is what i remember.. 1. aproach is simple to keep track of max rectangle which can be formed from any point taking that point as top left corner of max rectangle and proceed further down . can someone suggest how can be proceed further.. [ NOTE: problem occurs mainly when their are more than one rectangles which can be formed from same point ] plz.. don't suggest the histogram method it's just a dirty way of avoiding to work on getting this DP right. :-) On Mon, Mar 12, 2012 at 11:29 PM, atul anand atul.87fri...@gmail.com wrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.com wrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message
Re: [algogeeks] Maximum size square sub-matrix with all 1s
here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.comwrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
Re: [algogeeks] Maximum size square sub-matrix with all 1s
wats d logic behind this??? On Tue, Mar 13, 2012 at 11:59 AM, atul anand atul.87fri...@gmail.comwrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.comwrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
Re: [algogeeks] Maximum size square sub-matrix with all 1s
@ ALL finding square matrix is quite a standard question and nw an easy one as everyone knows the reccussence atul has given. but i wanted to find max rectangle.. i know there is a DP for it. in O(n^2). for nxn matrix..don't know the whole approach .but here is what i remember.. 1. aproach is simple to keep track of max rectangle which can be formed from any point taking that point as top left corner of max rectangle and proceed further down . can someone suggest how can be proceed further.. [ NOTE: problem occurs mainly when their are more than one rectangles which can be formed from same point ] plz.. don't suggest the histogram method it's just a dirty way of avoiding to work on getting this DP right. :-) On Mon, Mar 12, 2012 at 11:29 PM, atul anand atul.87fri...@gmail.comwrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.comwrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
Re: [algogeeks] Maximum size square sub-matrix with all 1s
@ Sourabh: check solution i have posted in below link http://groups.google.com/group/algogeeks/browse_thread/thread/91a17f7c78c2319e/991d1c2625a62ff0?hl=enlnk=gstq=rectangle+of+max+sum+MS+Q#991d1c2625a62ff0 On Tue, Mar 13, 2012 at 10:26 PM, Sourabh Singh singhsourab...@gmail.comwrote: @ ALL finding square matrix is quite a standard question and nw an easy one as everyone knows the reccussence atul has given. but i wanted to find max rectangle.. i know there is a DP for it. in O(n^2). for nxn matrix..don't know the whole approach .but here is what i remember.. 1. aproach is simple to keep track of max rectangle which can be formed from any point taking that point as top left corner of max rectangle and proceed further down . can someone suggest how can be proceed further.. [ NOTE: problem occurs mainly when their are more than one rectangles which can be formed from same point ] plz.. don't suggest the histogram method it's just a dirty way of avoiding to work on getting this DP right. :-) On Mon, Mar 12, 2012 at 11:29 PM, atul anand atul.87fri...@gmail.comwrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.comwrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
Re: [algogeeks] Maximum size square sub-matrix with all 1s
@atul read it .. it's good but more or less like the histogram algo.. i wanted a DP. approach.. here is some of wat i heard from a senior in colg.. 1. at every index we can keep 4 variable ht: height of max rectangle possible at index above current wt width hl:height of max rectangle possible at index left of current wl: now problem is which one to take for current... index On Tue, Mar 13, 2012 at 10:52 AM, atul anand atul.87fri...@gmail.comwrote: @ Sourabh: check solution i have posted in below link http://groups.google.com/group/algogeeks/browse_thread/thread/91a17f7c78c2319e/991d1c2625a62ff0?hl=enlnk=gstq=rectangle+of+max+sum+MS+Q#991d1c2625a62ff0 On Tue, Mar 13, 2012 at 10:26 PM, Sourabh Singh singhsourab...@gmail.comwrote: @ ALL finding square matrix is quite a standard question and nw an easy one as everyone knows the reccussence atul has given. but i wanted to find max rectangle.. i know there is a DP for it. in O(n^2). for nxn matrix..don't know the whole approach .but here is what i remember.. 1. aproach is simple to keep track of max rectangle which can be formed from any point taking that point as top left corner of max rectangle and proceed further down . can someone suggest how can be proceed further.. [ NOTE: problem occurs mainly when their are more than one rectangles which can be formed from same point ] plz.. don't suggest the histogram method it's just a dirty way of avoiding to work on getting this DP right. :-) On Mon, Mar 12, 2012 at 11:29 PM, atul anand atul.87fri...@gmail.comwrote: here is the recurrence for solving this R[i, j] = (M[i,j] == 0 ? 0 : 1 + min( R[i-1, j], R[i-1, j-1], R[i,,j-1] ) ); On Tue, Mar 13, 2012 at 11:48 AM, rahul sharma rahul23111...@gmail.comwrote: April 4, 2010 Given a binary matrix, find out the maximum size square sub-matrix with all 1s. For example, consider the below binary matrix. 0 1 1 0 1 1 1 0 1 0 0 1 1 1 0 1 1 1 1 0 1 1 1 1 1 0 0 0 0 0 The maximum square sub-matrix with all set bits is 1 1 1 1 1 1 1 1 1 -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
Re: [algogeeks] Maximum size square sub-matrix with all 1s
i dint get...you should provide more details , if it is all 1 then whole matrix is a max square.. anyways equation to find max sub square is this. M[i,j]=R[i,j]==0 ? 0 : 1+min(M[i-1][,j] , M[i][j-1], M[i-1][j-1] ) On Tue, Jan 10, 2012 at 10:00 PM, Sanjay Rajpal sanjay.raj...@live.inwrote: Suggest an algorithm guyzzz. * Sanjay Kumar B.Tech Final Year Department of Computer Engineering National Institute of Technology Kurukshetra Kurukshetra - 136119 Haryana, India Contact: +91-8053566286 * -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
Re: [algogeeks] Maximum size square sub-matrix with all 1s
Its a square matrix containing 0s and 1s. Will u plz elaborate about this equation ? * Sanjay Kumar B.Tech Final Year Department of Computer Engineering National Institute of Technology Kurukshetra Kurukshetra - 136119 Haryana, India Contact: +91-8053566286 * On Tue, Jan 10, 2012 at 8:36 AM, atul anand atul.87fri...@gmail.com wrote: i dint get...you should provide more details , if it is all 1 then whole matrix is a max square.. anyways equation to find max sub square is this. M[i,j]=R[i,j]==0 ? 0 : 1+min(M[i-1][,j] , M[i][j-1], M[i-1][j-1] ) On Tue, Jan 10, 2012 at 10:00 PM, Sanjay Rajpal sanjay.raj...@live.inwrote: Suggest an algorithm guyzzz. * Sanjay Kumar B.Tech Final Year Department of Computer Engineering National Institute of Technology Kurukshetra Kurukshetra - 136119 Haryana, India Contact: +91-8053566286 * -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en. -- You received this message because you are subscribed to the Google Groups Algorithm Geeks group. To post to this group, send email to algogeeks@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.