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 13:15highload-churnerhighload-churnerScore: 1,862Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 19, 2026 13:171,72011,574,756688,000024,576stderr
2Oct 19, 2026 13:171,82210,033,773729,000024,576stderr
3Oct 19, 2026 13:171,85710,146,316743,000024,576stderr
4Oct 19, 2026 13:171,8609,724,156744,000024,576stderr
5Oct 19, 2026 13:171,8629,749,117745,000024,576stderr
6Oct 19, 2026 13:171,8709,742,266748,000024,576stderr
7Oct 19, 2026 13:171,88210,083,647753,000024,576stderr
8Oct 19, 2026 13:171,90510,149,221762,000024,576stderr
9Oct 19, 2026 13:172,0879,894,859835,000024,576stderr