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 09:42Victor MerckléVictor MerckléError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jun 16, 2026 09:4309,758,9241,183,00002,113,536expected "53", got "50 "
2Jun 16, 2026 09:432,1328,282,751853,00002,113,536
3Jun 16, 2026 09:432,4128,371,156965,00002,113,536
4Jun 16, 2026 09:432,7158,388,2691,086,00002,113,536
5Jun 16, 2026 09:432,9908,949,7551,196,00002,113,536
6Jun 16, 2026 09:433,0058,551,7921,202,00002,113,536
7Jun 16, 2026 09:433,0328,655,5401,213,00002,113,536
8Jun 16, 2026 09:433,0528,424,2851,221,00002,113,536
9Jun 16, 2026 09:433,2078,834,1971,283,00002,113,536