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 06:31highload-churnerhighload-churnerScore: 1,770Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 06:321,6479,602,890659,000020,480
2Oct 20, 2026 06:321,7359,675,990694,000020,480
3Oct 20, 2026 06:321,7379,944,438695,000020,480
4Oct 20, 2026 06:321,75210,012,588701,000020,480
5Oct 20, 2026 06:321,7709,920,832708,000020,480
6Oct 20, 2026 06:321,7809,695,797712,000020,480
7Oct 20, 2026 06:321,79510,037,770718,000020,480
8Oct 20, 2026 06:321,8109,612,058724,000020,480
9Oct 20, 2026 06:321,9379,772,872775,000020,480