Largest Square Submatrix of all 1's NoSIMD_C#

Find the largest square submatrix consisting entirely of 1s as fast as possible.

Input

A 10,000 x 10,000 matrix of uint8 values (0 or 1) on STDIN.

0, 1, 0, 1, 1
0, 1, 1, 1, 1
0, 0, 1, 0, 0
1, 0, 1, 1, 0

Output

Print the side length of the largest all-ones square submatrix to STDOUT. The answer is guaranteed to be greater than 1.

For the example above, the output is:

2
Back to listJan 3, 2026 04:58Josu San MartinJosu San MartinScore: 5,400Success
Source Code

Source code access is restricted. Log in to request access.

Challenge History

No challenges yet.

Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jan 3, 2026 05:025,10016,881,9341,020,0001,020,0002,281,472
2Jan 3, 2026 05:015,30519,125,22702,122,0002,445,312
3Jan 3, 2026 05:025,38517,050,29902,154,0002,277,376
4Jan 3, 2026 05:015,39519,754,28702,158,0002,441,216
5Jan 3, 2026 05:025,40019,394,72202,160,0002,449,408
6Jan 3, 2026 05:015,59014,725,2361,118,0001,118,0002,449,408
7Jan 3, 2026 04:585,87819,154,69402,351,0002,449,408
8Jan 3, 2026 04:586,02521,638,7371,205,0001,205,0002,277,376
9Jan 3, 2026 04:586,30518,247,6581,261,0001,261,0002,441,216