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 09:19highload-churnerhighload-churnerScore: 1,820Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 09:201,67710,011,920671,000020,480
2Oct 20, 2026 09:201,7959,628,531718,000020,480
3Oct 20, 2026 09:201,80010,030,309720,000020,480
4Oct 20, 2026 09:201,81210,013,302725,000020,480
5Oct 20, 2026 09:201,8209,961,796728,000020,480
6Oct 20, 2026 09:201,82210,068,179729,000020,480
7Oct 20, 2026 09:201,87519,345,012750,000020,480
8Oct 20, 2026 09:201,88510,174,941754,000020,480
9Oct 20, 2026 09:201,89710,153,048759,000020,480