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 14:43highload-churnerhighload-churnerScore: 6,072Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 19, 2026 14:445,15011,297,4272,060,000024,576stderr
2Oct 19, 2026 14:445,20711,288,6262,083,000024,576stderr
3Oct 19, 2026 14:445,54711,503,9652,219,000024,576stderr
4Oct 19, 2026 14:445,81711,600,3832,327,000024,576stderr
5Oct 19, 2026 14:446,07213,595,3322,429,000024,576stderr
6Oct 19, 2026 14:446,10711,594,1872,443,000024,576stderr
7Oct 19, 2026 14:446,10712,051,5392,443,000024,576stderr
8Oct 19, 2026 14:446,13211,659,3512,453,000024,576stderr
9Oct 19, 2026 14:446,18212,172,8992,473,000024,576stderr