OJ Board

Here there are some test cases you might try. The solution is in http://www.udebug.com/UVa/12782 :
1 2 3 4 5 6 7 8 9
1 14 4 14 11 7 6 9 8 13 10 2 10 3 5 15
4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 8
1 2 3 4
1 1 -1 -1
1 1 1 1
-1 -1 -1 -1
1 1 1
0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
1 2 3 1 2 ...

Hi,

I have tried this problem using Backtracking with pruning in C++, but so far my code is not fast enough.

The pruning I do is the following(lets call N the amount of numbers, nn the square root of N, S the modulo of the Magic Square):
- if N==1, then Yes
- otherwise if N!=4 && N!=9 && N!=16 ...

Hi, Everyone,

I don't know for you, but for me this problem was a little bit tricky and the previous forum replies were not helpful enough. Here some Tips:

1- As suggested for this problem (and I recommend it also for all problems), you should use static arrays a little bit larger than the limits ...