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 19, 2026 13:13highload-churnerhighload-churnerScore: 1,875Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 19, 2026 13:141,7179,691,313687,000024,576stderr
2Oct 19, 2026 13:141,80510,064,450722,000024,576stderr
3Oct 19, 2026 13:141,8109,728,690724,000024,576stderr
4Oct 19, 2026 13:141,8509,793,207740,000024,576stderr
5Oct 19, 2026 13:141,8759,737,054750,000024,576stderr
6Oct 19, 2026 13:141,8779,783,515751,000024,576stderr
7Oct 19, 2026 13:141,89710,209,081759,000024,576stderr
8Oct 19, 2026 13:141,90010,107,679760,000024,576stderr
9Oct 19, 2026 13:141,9129,758,304765,000024,576stderr