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 17, 2026 03:26Victor MerckléVictor MerckléError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jun 17, 2026 03:2709,018,8211,496,00002,113,536expected "65", got "50 "
2Jun 17, 2026 03:271,7408,115,082696,00002,113,536
3Jun 17, 2026 03:271,9708,241,667788,00002,113,536
4Jun 17, 2026 03:272,6078,447,4431,043,00002,113,536
5Jun 17, 2026 03:273,6728,983,8821,469,00002,113,536
6Jun 17, 2026 03:274,0679,034,7501,627,00002,113,536
7Jun 17, 2026 03:274,0859,145,7121,634,00002,113,536
8Jun 17, 2026 03:274,1078,968,4031,643,00002,113,536
9Jun 17, 2026 03:274,3429,221,8451,737,00002,113,536