Largest Square Submatrix of all 1's Haha Expert

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 listOct 12, 2026 16:22highload-churnerhighload-churnerScore: 2,855Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 12, 2026 16:232,6179,769,0861,047,00002,117,632stderr
2Oct 12, 2026 16:232,7159,709,3861,086,00002,117,632stderr
3Oct 12, 2026 16:232,82210,262,3171,129,00002,117,632stderr
4Oct 12, 2026 16:232,8509,806,1861,140,00002,117,632stderr
5Oct 12, 2026 16:232,8559,776,4311,142,00002,117,632stderr
6Oct 12, 2026 16:232,8829,811,4561,153,00002,117,632stderr
7Oct 12, 2026 16:232,8929,803,3841,157,00002,117,632stderr
8Oct 12, 2026 16:233,0479,931,3711,219,00002,117,632stderr
9Oct 12, 2026 16:233,21210,033,3681,285,00002,117,632stderr