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 16, 2026 15:55Victor MerckléVictor MerckléError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jun 16, 2026 15:5608,715,9541,482,00002,113,536expected "66", got "50 "
2Jun 16, 2026 15:561,7678,142,650707,00002,113,536
3Jun 16, 2026 15:561,7928,162,265717,00002,113,536
4Jun 16, 2026 15:562,6308,331,2191,052,00002,113,536
5Jun 16, 2026 15:562,8378,658,2261,135,00002,113,536
6Jun 16, 2026 15:562,9028,631,2871,161,00002,113,536
7Jun 16, 2026 15:563,4758,888,4691,390,00002,113,536
8Jun 16, 2026 15:563,5528,748,3751,421,00002,113,536
9Jun 16, 2026 15:563,6378,789,9301,455,00002,113,536