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 listJul 6, 2026 00:16Victor MerckléVictor MerckléError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jul 6, 2026 00:1908,770,6861,010,00002,117,632expected "81", got "50 "stderr
2Jul 6, 2026 00:192,2078,712,767883,00002,117,632stderr
3Jul 6, 2026 00:192,3578,723,816943,00002,117,632stderr
4Jul 6, 2026 00:192,3628,657,773945,00002,117,632stderr
5Jul 6, 2026 00:192,7158,745,0041,086,00002,117,632stderr
6Jul 6, 2026 00:192,8029,211,4671,121,00002,117,632stderr
7Jul 6, 2026 00:192,8028,808,7791,121,00002,117,632stderr
8Jul 6, 2026 00:192,8078,791,3251,123,00002,117,632stderr
9Jul 6, 2026 00:192,8659,256,6021,146,00002,117,632stderr