initial call to this function is arrange(arr,n/3,n/3) where n is actually 3*n as per the question , like n=30 for a1,...,a10,b1,...,b10,c1,....c10
The idea used here is that for some i-1 ranging from 1 to 9 for above example, i-1 goes to 3*(i-1), n+i-1 to 3*(i-1) +1, and 2*n+i-1 to 3*(i-1)+2.. recursive function calls are used void arrange(int arr[], int n, int i) { if(i == 1) { arr[1] = arr[n]; arr[2] = arr[2*n]; return; } int a = arr[i - 1]; int b = arr[n + i - 1]; int c = arr[2*n + i - 1]; arrange(arr, n, i - 1); int x = 3 * (i - 1); arr[x] = a; arr[x + 1] = b; arr[x + 2] = c; } On Sat, Oct 15, 2011 at 11:14 AM, Ankur Garg <ankurga...@gmail.com> wrote: > @Dan ..can you post the algo here or link to the book?? > @Anika ...yes please post the code here..but please explain a bit about > underlying algo ...(algo is more important than actual code ) > > > > On Sat, Oct 15, 2011 at 1:54 AM, Dan <dant...@aol.com> wrote: > >> On Oct 13, 7:52 pm, "shiva@Algo" <shiv.jays...@gmail.com> wrote: >> > Convert an array "a1 a2 a3...an b1 b2 b3...bn c1 c2 c3...cn" to "a1b1c1 >> > a2b2c2...anbncn", inplace >> >> >> See the algorithm for memory efficient rearrangement of array elements >> in one of the books by Robert Sedgewick such as Algorithms in C++ or >> Algorithms in Pascal, etc. >> >> Dan >> >> -- >> 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.