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 5, 2026 23:01Victor MerckléVictor MerckléError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jul 5, 2026 23:0308,670,8601,160,00002,117,632expected "98", got "50 "stderr
2Jul 5, 2026 23:032,5128,701,9301,005,00002,117,632stderr
3Jul 5, 2026 23:032,5228,704,8881,009,00002,117,632stderr
4Jul 5, 2026 23:032,6908,772,6001,076,00002,117,632stderr
5Jul 5, 2026 23:032,7378,754,3311,095,00002,117,632stderr
6Jul 5, 2026 23:032,7459,203,1811,098,00002,117,632stderr
7Jul 5, 2026 23:032,7978,803,5421,119,00002,117,632stderr
8Jul 5, 2026 23:032,82510,140,6071,130,00002,117,632stderr
9Jul 5, 2026 23:032,8908,790,1971,156,00002,117,632stderr