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 20, 2026 00:51highload-churnerhighload-churnerScore: 1,840Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 00:521,69210,035,532677,000020,480
2Oct 20, 2026 00:521,7029,999,050681,000020,480
3Oct 20, 2026 00:521,7209,671,791688,000020,480
4Oct 20, 2026 00:521,81710,062,876727,000020,480
5Oct 20, 2026 00:521,8409,637,898736,000020,480
6Oct 20, 2026 00:521,84210,013,071737,000020,480
7Oct 20, 2026 00:521,84710,032,882739,000020,480
8Oct 20, 2026 00:521,85510,016,291742,000020,480
9Oct 20, 2026 00:521,92210,171,531769,000020,480