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 05:33highload-churnerhighload-churnerScore: 2,930Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 05:342,82710,162,3291,131,000024,576stderr
2Oct 20, 2026 05:342,83710,141,5161,135,000024,576stderr
3Oct 20, 2026 05:342,90710,142,5911,163,000024,576stderr
4Oct 20, 2026 05:342,92510,695,1451,170,000024,576stderr
5Oct 20, 2026 05:342,93010,265,2731,172,000024,576stderr
6Oct 20, 2026 05:342,95010,720,7861,180,000024,576stderr
7Oct 20, 2026 05:342,96510,649,2041,186,000024,576stderr
8Oct 20, 2026 05:342,98010,740,9381,192,000024,576stderr
9Oct 20, 2026 05:343,03710,369,5691,215,000024,576stderr