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 listJun 15, 2026 19:00Victor MerckléVictor MerckléError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jun 15, 2026 19:0108,472,6841,142,00002,113,536expected "96", got "50 "
2Jun 15, 2026 19:011,9608,205,297784,00002,113,536
3Jun 15, 2026 19:012,0078,171,543803,00002,113,536
4Jun 15, 2026 19:012,1778,191,549871,00002,113,536
5Jun 15, 2026 19:012,3308,323,696932,00002,113,536
6Jun 15, 2026 19:012,5908,369,2491,036,00002,113,536
7Jun 15, 2026 19:012,7708,549,9351,108,00002,113,536
8Jun 15, 2026 19:012,8228,446,5551,129,00002,113,536
9Jun 15, 2026 19:012,8778,496,4221,151,00002,113,536