Re: [algogeeks] Re: Least fare for a return trip Algorithm

2010-10-29 Thread Harish U
@amod

I am not sure I understand what you are saying.
It is assumed that the K smallest Items(from both list A  B) are identified
and arranged in increasing order as the first step.

Now A(1) and B(1) constitute the least fare round trip(since the list is
sorted) and we include that combination into our list of selected round
trips with minimal fare. Then we proceed by either including A(1)-B(2) or
A(2)-B(1) or both (if they add up to an equal value)
I am not clear about what you mean by reuse of elements.
Am I missing anything here  ? If so a more clear example would help !

On Thu, Oct 28, 2010 at 10:26 AM, Amod gam...@gmail.com wrote:

 @Algoose
 Yes, but the algoritm is not correct since we are not covering the
 condition where element is reused.
 Ex ia=1 and ib=1
 If we increment ia to 2 then there may be a case where A(1)+B(1) is
 less than A(2)+B(1) but since 1 was denoted by ia which is now 2 hence
 we will never be able to check this.
 So algorithm ignores reuse of elements.


 On Oct 27, 5:06 pm, Algoose chase harishp...@gmail.com wrote:
  @Dave,
 
  I believe in the first if clause ib must be incremented
  in the else if clause ia must be incremented.
 
  is that right ?
 
 
 
  On Sat, Oct 16, 2010 at 6:21 PM, Dave dave_and_da...@juno.com wrote:
   @Coolfrog$:
 
   1. No. It should be O(n + k log k) because finding the kth smallest
   element of an array of size n is O(n), using the Median of Medians
   algorithm; see
  http://en.wikipedia.org/wiki/Median_algorithm#Linear_general_selectio.
 ..
   .
 
   2. Assuming that the entries in A are distinct and so are the entries
   in B, we can handle the equality of sums case:
 
   find the smallest k elements of A and sort them into ascending order.
   find the smallest k elements of B and sort them into ascending order.
   ia = 1
   ib = 1
   output ia, ib, A(ia)+B(ib)
   for n = 1 to k do
  if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
  ia = ia + 1
  output ia, ib, A(ia)+B(ib)
   else if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
  ib = ib + 1
   output ia, ib, A(ia)+B(ib)
   else // equality case
  ia = ia + 1
  ib = ib + 1
  output ia-1, ib, A(ia-1)+B(ib)
  output ia, ib-1, A(ia)+B(ib-1)
  end if
   end for
 
   Dave
 
   On Oct 16, 6:20 am, coolfrog$ dixit.coolfrog.div...@gmail.com
   wrote:
@Dave
  1. should it not be O(k + klogk) ??
  2. but u are not considering all the possible values... let k =3
like   i.  a1+b1
ii.  min( a1+b2, a2+b1)  upto these fine one of them will
 be
chosen ...either ia or ib will increase.
iii. but know we have to take  remaining of step ii in to
consideration along with
 a1+b3,a3+b1,a2+b3,a3+b2 ...
 
On Fri, Oct 15, 2010 at 8:20 PM, Dave dave_and_da...@juno.com
 wrote:
 @Coolfrog$: You don't have to sort the arrays. You only have to
 find
 the k smallest elements in each and sort those k entries. This can
 be
 done in O(n + k log k).
 
 Algorithm:
 find the smallest k elements of A and sort them into ascending
 order.
 find the smallest k elements of B and sort them into ascending
 order.
 ia = 1
 ib = 1
 output ia, ib, A(ia)+B(ib)
 for n = 1 to k do
if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
ia = ia + 1
else
ib = ib + 1
end if
output ia, ib, A(ia)+B(ib)
 end for
 
 Complexity O(n + k log k).
 
 Dave
 
 On Oct 15, 4:00 am, coolfrog$ dixit.coolfrog.div...@gmail.com
 wrote:
  @amod
   as given   A-B  andB-A are in sorted form...if not
 sort
   them
 in
  O(n log n).
  then
first suggestion  A1+B1
 second suggestion  MIN( A1+B2 , B1+A2) === let it be B1+A2
third suggestion  MIN( A1+B2 , A1+B3, A3+B1,A2+B3, A3+B2)
 let
   it
 be
  A2+B3
 and so on...
 
  @Dave what will be complexity of above solution...?
  i think O(n log n) for sorting and second part (suggestions)
   O(n)..
 
  Guys do correct me plz...
 
  On Thu, Oct 14, 2010 at 11:10 AM, Amod gam...@gmail.com wrote:
   @Dave  You are partly correct.
 
   If i ask for four minimum fares for the round trip then
   first suggestion is what u said : sum the sum of the minimum
 cost
   from
   A to B and the minimum cost from B to A
   after that we have to see which combination from both costs,
 sums
   up
   least
 
   On Oct 14, 9:55 am, Dave dave_and_da...@juno.com wrote:
@Amod. Isn't the minimum sum the sum of the minimum cost from
 A
   to B
and the minimum cost from B to A? What am I missing?
 
Dave
 
On Oct 13, 11:06 pm, Amod gam...@gmail.com wrote:
 
 Hi
 
 I think I forgot to mention that the SUM of the ROUND trip
 i.e.
 A-B-A
(sum = going + returning) should be least.
 
 Please 

[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-17 Thread Amod
@Dave I tried to run your algorithm but I am not getting the desired
results

Taking inputs as given by @coolfrog
AB
16
37
69

I am getting
AB Sum
167
369
66   12
96   15

and the desired output would have been

1 6 7
1 7 8
3 6 9
1 9 10
6 6 12

I think we are not covering the point where index is reused.
If we increment the index by one the the condition like 1 7 8 will not
occur.

Please suggest.

Amod

On Oct 16, 5:51 pm, Dave dave_and_da...@juno.com wrote:
 @Coolfrog$:

 1. No. It should be O(n + k log k) because finding the kth smallest
 element of an array of size n is O(n), using the Median of Medians
 algorithm; 
 seehttp://en.wikipedia.org/wiki/Median_algorithm#Linear_general_selectio

 2. Assuming that the entries in A are distinct and so are the entries
 in B, we can handle the equality of sums case:

 find the smallest k elements of A and sort them into ascending order.
 find the smallest k elements of B and sort them into ascending order.
 ia = 1
 ib = 1
 output ia, ib, A(ia)+B(ib)
 for n = 1 to k do
     if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
         ia = ia + 1
         output ia, ib, A(ia)+B(ib)
     else if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
         ib = ib + 1
         output ia, ib, A(ia)+B(ib)
     else // equality case
         ia = ia + 1
         ib = ib + 1
         output ia-1, ib, A(ia-1)+B(ib)
         output ia, ib-1, A(ia)+B(ib-1)
     end if
 end for

 Dave

 On Oct 16, 6:20 am, coolfrog$ dixit.coolfrog.div...@gmail.com
 wrote:



  @Dave
    1. should it not be O(k + klogk) ??
    2. but u are not considering all the possible values... let k =3
      like   i.  a1+b1
              ii.  min( a1+b2, a2+b1)  upto these fine one of them will be
  chosen ...either ia or ib will increase.
              iii. but know we have to take  remaining of step ii in to
  consideration along with
                   a1+b3,a3+b1,a2+b3,a3+b2 ...

  On Fri, Oct 15, 2010 at 8:20 PM, Dave dave_and_da...@juno.com wrote:
   @Coolfrog$: You don't have to sort the arrays. You only have to find
   the k smallest elements in each and sort those k entries. This can be
   done in O(n + k log k).

   Algorithm:
   find the smallest k elements of A and sort them into ascending order.
   find the smallest k elements of B and sort them into ascending order.
   ia = 1
   ib = 1
   output ia, ib, A(ia)+B(ib)
   for n = 1 to k do
      if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
          ia = ia + 1
      else
          ib = ib + 1
      end if
      output ia, ib, A(ia)+B(ib)
   end for

   Complexity O(n + k log k).

   Dave

   On Oct 15, 4:00 am, coolfrog$ dixit.coolfrog.div...@gmail.com
   wrote:
@amod
 as given   A-B      and    B-A are in sorted form...if not sort them
   in
O(n log n).
then
      first suggestion  A1+B1
   second suggestion  MIN( A1+B2 , B1+A2) === let it be B1+A2
  third suggestion  MIN( A1+B2 , A1+B3, A3+B1,A2+B3, A3+B2) let it
   be
A2+B3
   and so on...

@Dave what will be complexity of above solution...?
    i think O(n log n) for sorting and second part (suggestions) O(n)..

Guys do correct me plz...

On Thu, Oct 14, 2010 at 11:10 AM, Amod gam...@gmail.com wrote:
 @Dave  You are partly correct.

 If i ask for four minimum fares for the round trip then
 first suggestion is what u said : sum the sum of the minimum cost from
 A to B and the minimum cost from B to A
 after that we have to see which combination from both costs, sums up
 least

 On Oct 14, 9:55 am, Dave dave_and_da...@juno.com wrote:
  @Amod. Isn't the minimum sum the sum of the minimum cost from A to B
  and the minimum cost from B to A? What am I missing?

  Dave

  On Oct 13, 11:06 pm, Amod gam...@gmail.com wrote:

   Hi

   I think I forgot to mention that the SUM of the ROUND trip i.e.
   A-B-A
  (sum = going + returning) should be least.

   Please don't take into account any other thing like time and
   availability.
   So solution is not that straightforward.

   Its like we have two arrays and we have to return least k sum from
   the
   given arrays where we take one element from the first and one from
   second in the sum.

   Cheers
   Amod

   On Oct 13, 2:26 pm, Shiyam code_for_life mailshyamh...@gmail.com
   wrote:

When a user wants to choose to fly from A to B, suggest the
   flight
with lowest fare that's available, here its A1, if A1 is busy
   then A2
and so on
Repeat the same for B to A.

Am I missing something here?

Complexity is O( (number of flights from A to B) + number of
   flights
from B to A) )

Cheers

'Coding is an art'- Hide quoted text -

   - Show quoted text -

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Re: [algogeeks] Re: Least fare for a return trip Algorithm

2010-10-16 Thread coolfrog$
@Dave
  1. should it not be O(k + klogk) ??
  2. but u are not considering all the possible values... let k =3
like   i.  a1+b1
ii.  min( a1+b2, a2+b1)  upto these fine one of them will be
chosen ...either ia or ib will increase.
iii. but know we have to take  remaining of step ii in to
consideration along with
 a1+b3,a3+b1,a2+b3,a3+b2 ...
On Fri, Oct 15, 2010 at 8:20 PM, Dave dave_and_da...@juno.com wrote:

 @Coolfrog$: You don't have to sort the arrays. You only have to find
 the k smallest elements in each and sort those k entries. This can be
 done in O(n + k log k).

 Algorithm:
 find the smallest k elements of A and sort them into ascending order.
 find the smallest k elements of B and sort them into ascending order.
 ia = 1
 ib = 1
 output ia, ib, A(ia)+B(ib)
 for n = 1 to k do
if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
ia = ia + 1
else
ib = ib + 1
end if
output ia, ib, A(ia)+B(ib)
 end for

 Complexity O(n + k log k).

 Dave


 On Oct 15, 4:00 am, coolfrog$ dixit.coolfrog.div...@gmail.com
 wrote:
  @amod
   as given   A-B  andB-A are in sorted form...if not sort them
 in
  O(n log n).
  then
first suggestion  A1+B1
 second suggestion  MIN( A1+B2 , B1+A2) === let it be B1+A2
third suggestion  MIN( A1+B2 , A1+B3, A3+B1,A2+B3, A3+B2) let it
 be
  A2+B3
 and so on...
 
  @Dave what will be complexity of above solution...?
  i think O(n log n) for sorting and second part (suggestions) O(n)..
 
  Guys do correct me plz...
 
 
 
 
 
  On Thu, Oct 14, 2010 at 11:10 AM, Amod gam...@gmail.com wrote:
   @Dave  You are partly correct.
 
   If i ask for four minimum fares for the round trip then
   first suggestion is what u said : sum the sum of the minimum cost from
   A to B and the minimum cost from B to A
   after that we have to see which combination from both costs, sums up
   least
 
   On Oct 14, 9:55 am, Dave dave_and_da...@juno.com wrote:
@Amod. Isn't the minimum sum the sum of the minimum cost from A to B
and the minimum cost from B to A? What am I missing?
 
Dave
 
On Oct 13, 11:06 pm, Amod gam...@gmail.com wrote:
 
 Hi
 
 I think I forgot to mention that the SUM of the ROUND trip i.e.
 A-B-A
(sum = going + returning) should be least.
 
 Please don't take into account any other thing like time and
 availability.
 So solution is not that straightforward.
 
 Its like we have two arrays and we have to return least k sum from
 the
 given arrays where we take one element from the first and one from
 second in the sum.
 
 Cheers
 Amod
 
 On Oct 13, 2:26 pm, Shiyam code_for_life mailshyamh...@gmail.com
 wrote:
 
  When a user wants to choose to fly from A to B, suggest the
 flight
  with lowest fare that's available, here its A1, if A1 is busy
 then A2
  and so on
  Repeat the same for B to A.
 
  Am I missing something here?
 
  Complexity is O( (number of flights from A to B) + number of
 flights
  from B to A) )
 
  Cheers
 
  'Coding is an art'- Hide quoted text -
 
 - Show quoted text -
 
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[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-16 Thread Dave
@Coolfrog$:

1. No. It should be O(n + k log k) because finding the kth smallest
element of an array of size n is O(n), using the Median of Medians
algorithm; see 
http://en.wikipedia.org/wiki/Median_algorithm#Linear_general_selection_algorithm_-_Median_of_Medians_algorithm.

2. Assuming that the entries in A are distinct and so are the entries
in B, we can handle the equality of sums case:

find the smallest k elements of A and sort them into ascending order.
find the smallest k elements of B and sort them into ascending order.
ia = 1
ib = 1
output ia, ib, A(ia)+B(ib)
for n = 1 to k do
if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
ia = ia + 1
output ia, ib, A(ia)+B(ib)
else if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
ib = ib + 1
output ia, ib, A(ia)+B(ib)
else // equality case
ia = ia + 1
ib = ib + 1
output ia-1, ib, A(ia-1)+B(ib)
output ia, ib-1, A(ia)+B(ib-1)
end if
end for

Dave

On Oct 16, 6:20 am, coolfrog$ dixit.coolfrog.div...@gmail.com
wrote:
 @Dave
   1. should it not be O(k + klogk) ??
   2. but u are not considering all the possible values... let k =3
     like   i.  a1+b1
             ii.  min( a1+b2, a2+b1)  upto these fine one of them will be
 chosen ...either ia or ib will increase.
             iii. but know we have to take  remaining of step ii in to
 consideration along with
                  a1+b3,a3+b1,a2+b3,a3+b2 ...





 On Fri, Oct 15, 2010 at 8:20 PM, Dave dave_and_da...@juno.com wrote:
  @Coolfrog$: You don't have to sort the arrays. You only have to find
  the k smallest elements in each and sort those k entries. This can be
  done in O(n + k log k).

  Algorithm:
  find the smallest k elements of A and sort them into ascending order.
  find the smallest k elements of B and sort them into ascending order.
  ia = 1
  ib = 1
  output ia, ib, A(ia)+B(ib)
  for n = 1 to k do
     if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
         ia = ia + 1
     else
         ib = ib + 1
     end if
     output ia, ib, A(ia)+B(ib)
  end for

  Complexity O(n + k log k).

  Dave

  On Oct 15, 4:00 am, coolfrog$ dixit.coolfrog.div...@gmail.com
  wrote:
   @amod
    as given   A-B      and    B-A are in sorted form...if not sort them
  in
   O(n log n).
   then
         first suggestion  A1+B1
      second suggestion  MIN( A1+B2 , B1+A2) === let it be B1+A2
     third suggestion  MIN( A1+B2 , A1+B3, A3+B1,A2+B3, A3+B2) let it
  be
   A2+B3
      and so on...

   @Dave what will be complexity of above solution...?
       i think O(n log n) for sorting and second part (suggestions) O(n)..

   Guys do correct me plz...

   On Thu, Oct 14, 2010 at 11:10 AM, Amod gam...@gmail.com wrote:
@Dave  You are partly correct.

If i ask for four minimum fares for the round trip then
first suggestion is what u said : sum the sum of the minimum cost from
A to B and the minimum cost from B to A
after that we have to see which combination from both costs, sums up
least

On Oct 14, 9:55 am, Dave dave_and_da...@juno.com wrote:
 @Amod. Isn't the minimum sum the sum of the minimum cost from A to B
 and the minimum cost from B to A? What am I missing?

 Dave

 On Oct 13, 11:06 pm, Amod gam...@gmail.com wrote:

  Hi

  I think I forgot to mention that the SUM of the ROUND trip i.e.
  A-B-A
 (sum = going + returning) should be least.

  Please don't take into account any other thing like time and
  availability.
  So solution is not that straightforward.

  Its like we have two arrays and we have to return least k sum from
  the
  given arrays where we take one element from the first and one from
  second in the sum.

  Cheers
  Amod

  On Oct 13, 2:26 pm, Shiyam code_for_life mailshyamh...@gmail.com
  wrote:

   When a user wants to choose to fly from A to B, suggest the
  flight
   with lowest fare that's available, here its A1, if A1 is busy
  then A2
   and so on
   Repeat the same for B to A.

   Am I missing something here?

   Complexity is O( (number of flights from A to B) + number of
  flights
   from B to A) )

   Cheers

   'Coding is an art'- Hide quoted text -

  - Show quoted text -

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     `·.¸(¨`·.·´¨ ) Keep
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Re: [algogeeks] Re: Least fare for a return trip Algorithm

2010-10-16 Thread coolfrog$
@Dave
input: k=3
AB
16
37
69

output should be  (1,1,7), (1,2,8), (2,1,9)
im getting output form above code
(1,1,7)
   (2,1,9)
   (3,1,12)
Dave i am still learning algorithms .. so if i am wrong.. don't be annoyed
plz
thankyou in advance... take care..
On Sat, Oct 16, 2010 at 6:21 PM, Dave dave_and_da...@juno.com wrote:

 @Coolfrog$:

 1. No. It should be O(n + k log k) because finding the kth smallest
 element of an array of size n is O(n), using the Median of Medians
 algorithm; see
 http://en.wikipedia.org/wiki/Median_algorithm#Linear_general_selection_algorithm_-_Median_of_Medians_algorithm
 .

 2. Assuming that the entries in A are distinct and so are the entries
 in B, we can handle the equality of sums case:

 find the smallest k elements of A and sort them into ascending order.
 find the smallest k elements of B and sort them into ascending order.
 ia = 1
 ib = 1
 output ia, ib, A(ia)+B(ib)
 for n = 1 to k do
if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
ia = ia + 1
output ia, ib, A(ia)+B(ib)
 else if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
ib = ib + 1
 output ia, ib, A(ia)+B(ib)
 else // equality case
ia = ia + 1
ib = ib + 1
output ia-1, ib, A(ia-1)+B(ib)
output ia, ib-1, A(ia)+B(ib-1)
end if
 end for

 Dave

 On Oct 16, 6:20 am, coolfrog$ dixit.coolfrog.div...@gmail.com
 wrote:
  @Dave
1. should it not be O(k + klogk) ??
2. but u are not considering all the possible values... let k =3
  like   i.  a1+b1
  ii.  min( a1+b2, a2+b1)  upto these fine one of them will be
  chosen ...either ia or ib will increase.
  iii. but know we have to take  remaining of step ii in to
  consideration along with
   a1+b3,a3+b1,a2+b3,a3+b2 ...
 
 
 
 
 
  On Fri, Oct 15, 2010 at 8:20 PM, Dave dave_and_da...@juno.com wrote:
   @Coolfrog$: You don't have to sort the arrays. You only have to find
   the k smallest elements in each and sort those k entries. This can be
   done in O(n + k log k).
 
   Algorithm:
   find the smallest k elements of A and sort them into ascending order.
   find the smallest k elements of B and sort them into ascending order.
   ia = 1
   ib = 1
   output ia, ib, A(ia)+B(ib)
   for n = 1 to k do
  if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
  ia = ia + 1
  else
  ib = ib + 1
  end if
  output ia, ib, A(ia)+B(ib)
   end for
 
   Complexity O(n + k log k).
 
   Dave
 
   On Oct 15, 4:00 am, coolfrog$ dixit.coolfrog.div...@gmail.com
   wrote:
@amod
 as given   A-B  andB-A are in sorted form...if not sort
 them
   in
O(n log n).
then
  first suggestion  A1+B1
   second suggestion  MIN( A1+B2 , B1+A2) === let it be B1+A2
  third suggestion  MIN( A1+B2 , A1+B3, A3+B1,A2+B3, A3+B2) let
 it
   be
A2+B3
   and so on...
 
@Dave what will be complexity of above solution...?
i think O(n log n) for sorting and second part (suggestions)
 O(n)..
 
Guys do correct me plz...
 
On Thu, Oct 14, 2010 at 11:10 AM, Amod gam...@gmail.com wrote:
 @Dave  You are partly correct.
 
 If i ask for four minimum fares for the round trip then
 first suggestion is what u said : sum the sum of the minimum cost
 from
 A to B and the minimum cost from B to A
 after that we have to see which combination from both costs, sums
 up
 least
 
 On Oct 14, 9:55 am, Dave dave_and_da...@juno.com wrote:
  @Amod. Isn't the minimum sum the sum of the minimum cost from A
 to B
  and the minimum cost from B to A? What am I missing?
 
  Dave
 
  On Oct 13, 11:06 pm, Amod gam...@gmail.com wrote:
 
   Hi
 
   I think I forgot to mention that the SUM of the ROUND trip i.e.
   A-B-A
  (sum = going + returning) should be least.
 
   Please don't take into account any other thing like time and
   availability.
   So solution is not that straightforward.
 
   Its like we have two arrays and we have to return least k sum
 from
   the
   given arrays where we take one element from the first and one
 from
   second in the sum.
 
   Cheers
   Amod
 
   On Oct 13, 2:26 pm, Shiyam code_for_life 
 mailshyamh...@gmail.com
   wrote:
 
When a user wants to choose to fly from A to B, suggest the
   flight
with lowest fare that's available, here its A1, if A1 is busy
   then A2
and so on
Repeat the same for B to A.
 
Am I missing something here?
 
Complexity is O( (number of flights from A to B) + number of
   flights
from B to A) )
 
Cheers
 
'Coding is an art'- Hide quoted text -
 
   - Show quoted text -
 
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[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-15 Thread Dave
@Coolfrog$: You don't have to sort the arrays. You only have to find
the k smallest elements in each and sort those k entries. This can be
done in O(n + k log k).

Algorithm:
find the smallest k elements of A and sort them into ascending order.
find the smallest k elements of B and sort them into ascending order.
ia = 1
ib = 1
output ia, ib, A(ia)+B(ib)
for n = 1 to k do
if A(ia + 1) + B(ib)  A(ia) + B(ib + 1) then
ia = ia + 1
else
ib = ib + 1
end if
output ia, ib, A(ia)+B(ib)
end for

Complexity O(n + k log k).

Dave


On Oct 15, 4:00 am, coolfrog$ dixit.coolfrog.div...@gmail.com
wrote:
 @amod
  as given   A-B      and    B-A are in sorted form...if not sort them in
 O(n log n).
 then
       first suggestion  A1+B1
    second suggestion  MIN( A1+B2 , B1+A2) === let it be B1+A2
   third suggestion  MIN( A1+B2 , A1+B3, A3+B1,A2+B3, A3+B2) let it be
 A2+B3
    and so on...

 @Dave what will be complexity of above solution...?
     i think O(n log n) for sorting and second part (suggestions) O(n)..

 Guys do correct me plz...





 On Thu, Oct 14, 2010 at 11:10 AM, Amod gam...@gmail.com wrote:
  @Dave  You are partly correct.

  If i ask for four minimum fares for the round trip then
  first suggestion is what u said : sum the sum of the minimum cost from
  A to B and the minimum cost from B to A
  after that we have to see which combination from both costs, sums up
  least

  On Oct 14, 9:55 am, Dave dave_and_da...@juno.com wrote:
   @Amod. Isn't the minimum sum the sum of the minimum cost from A to B
   and the minimum cost from B to A? What am I missing?

   Dave

   On Oct 13, 11:06 pm, Amod gam...@gmail.com wrote:

Hi

I think I forgot to mention that the SUM of the ROUND trip i.e. A-B-A
   (sum = going + returning) should be least.

Please don't take into account any other thing like time and
availability.
So solution is not that straightforward.

Its like we have two arrays and we have to return least k sum from the
given arrays where we take one element from the first and one from
second in the sum.

Cheers
Amod

On Oct 13, 2:26 pm, Shiyam code_for_life mailshyamh...@gmail.com
wrote:

 When a user wants to choose to fly from A to B, suggest the flight
 with lowest fare that's available, here its A1, if A1 is busy then A2
 and so on
 Repeat the same for B to A.

 Am I missing something here?

 Complexity is O( (number of flights from A to B) + number of flights
 from B to A) )

 Cheers

 'Coding is an art'- Hide quoted text -

- Show quoted text -

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[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-13 Thread Shiyam code_for_life
When a user wants to choose to fly from A to B, suggest the flight
with lowest fare that's available, here its A1, if A1 is busy then A2
and so on
Repeat the same for B to A.

Am I missing something here?

Complexity is O( (number of flights from A to B) + number of flights
from B to A) )

Cheers

'Coding is an art'

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Re: [algogeeks] Re: Least fare for a return trip Algorithm

2010-10-13 Thread AlgoSau Sau
Although no inputs are given on flight timing (date and time) front but that
is one more factor that should be considered while scheduling the cheapest
round trip journey as it happens on travel sites normally

On Wed, Oct 13, 2010 at 2:56 PM, Shiyam code_for_life 
mailshyamh...@gmail.com wrote:

 When a user wants to choose to fly from A to B, suggest the flight
 with lowest fare that's available, here its A1, if A1 is busy then A2
 and so on
 Repeat the same for B to A.

 Am I missing something here?

 Complexity is O( (number of flights from A to B) + number of flights
 from B to A) )

 Cheers

 'Coding is an art'

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 Algorithm Geeks group.
 To post to this group, send email to algoge...@googlegroups.com.
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[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-13 Thread Amod
Hi

I think I forgot to mention that the SUM of the ROUND trip i.e. A-B-
A  (sum = going + returning) should be least.
Please don't take into account any other thing like time and
availability.
So solution is not that straightforward.

Its like we have two arrays and we have to return least k sum from the
given arrays where we take one element from the first and one from
second in the sum.

Cheers
Amod

On Oct 13, 2:26 pm, Shiyam code_for_life mailshyamh...@gmail.com
wrote:
 When a user wants to choose to fly from A to B, suggest the flight
 with lowest fare that's available, here its A1, if A1 is busy then A2
 and so on
 Repeat the same for B to A.

 Am I missing something here?

 Complexity is O( (number of flights from A to B) + number of flights
 from B to A) )

 Cheers

 'Coding is an art'

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[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-13 Thread Dave
@Amod. Isn't the minimum sum the sum of the minimum cost from A to B
and the minimum cost from B to A? What am I missing?

Dave

On Oct 13, 11:06 pm, Amod gam...@gmail.com wrote:
 Hi

 I think I forgot to mention that the SUM of the ROUND trip i.e. A-B-A  (sum 
 = going + returning) should be least.

 Please don't take into account any other thing like time and
 availability.
 So solution is not that straightforward.

 Its like we have two arrays and we have to return least k sum from the
 given arrays where we take one element from the first and one from
 second in the sum.

 Cheers
 Amod

 On Oct 13, 2:26 pm, Shiyam code_for_life mailshyamh...@gmail.com
 wrote:



  When a user wants to choose to fly from A to B, suggest the flight
  with lowest fare that's available, here its A1, if A1 is busy then A2
  and so on
  Repeat the same for B to A.

  Am I missing something here?

  Complexity is O( (number of flights from A to B) + number of flights
  from B to A) )

  Cheers

  'Coding is an art'- Hide quoted text -

 - Show quoted text -

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[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-12 Thread ligerdave
sorting is absolutely required. w/o the sorting, how are you going to
find the min? comparison is also a sorting algorithm.
it also depends on how many suggestions you wanna have. if it's just
the best deal, you can complete this in O(n+m) where n is the number
of different fares of trip to and m is the trip back

On Oct 12, 9:06 am, Amod gam...@gmail.com wrote:
 Suppose there are 100 flights from A to B and 1000 flights from B to
 A.
 Now a user selects the round trip from A to B and back to A, the site
 presents suggestions based on the least fare of the return journey.
 Could someone please help me to device and algorithm where based on
 number of suggestions   the results are displayed.
 ex
        A-B         B-A
 A1     1        B1    1
 A2     2        B2    3
 A3     4        B3    5
 A4     6        B4    8

 So if i want four suggestions then A1+B1, A2+B1, A1+B2, A2+B2

 Please also suggest whether sorting based on fares is required or not

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[algogeeks] Re: Least fare for a return trip Algorithm

2010-10-12 Thread Amod
Could you please elaborate on O(n+m) algorithm that you have used

On Oct 12, 6:43 pm, ligerdave david.c...@gmail.com wrote:
 sorting is absolutely required. w/o the sorting, how are you going to
 find the min? comparison is also a sorting algorithm.
 it also depends on how many suggestions you wanna have. if it's just
 the best deal, you can complete this in O(n+m) where n is the number
 of different fares of trip to and m is the trip back

 On Oct 12, 9:06 am, Amod gam...@gmail.com wrote:







  Suppose there are 100 flights from A to B and 1000 flights from B to
  A.
  Now a user selects the round trip from A to B and back to A, the site
  presents suggestions based on the least fare of the return journey.
  Could someone please help me to device and algorithm where based on
  number of suggestions   the results are displayed.
  ex
         A-B         B-A
  A1     1        B1    1
  A2     2        B2    3
  A3     4        B3    5
  A4     6        B4    8

  So if i want four suggestions then A1+B1, A2+B1, A1+B2, A2+B2

  Please also suggest whether sorting based on fares is required or not

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