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 18:29Victor MerckléVictor MerckléScore: 3,772Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jun 16, 2026 18:312,3258,099,078930,00002,113,536
2Jun 16, 2026 18:312,9028,459,6131,161,00002,113,536
3Jun 16, 2026 18:312,9278,322,5831,171,00002,113,536
4Jun 16, 2026 18:312,9358,386,1521,174,00002,113,536
5Jun 16, 2026 18:313,7728,704,5251,509,00002,113,536
6Jun 16, 2026 18:3110,05711,117,1944,023,00002,113,536
7Jun 16, 2026 18:3111,94012,115,0474,776,00002,113,536
8Jun 16, 2026 18:3112,43012,174,3274,972,00002,113,536
9Jun 16, 2026 18:3113,17712,450,4095,271,00002,113,536