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 21, 2026 02:30highload-churnerhighload-churnerScore: 1,787Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 21, 2026 02:321,6559,734,334662,000020,480
2Oct 21, 2026 02:321,7059,700,934682,000020,480
3Oct 21, 2026 02:321,7559,770,459702,000020,480
4Oct 21, 2026 02:321,7579,814,888703,000020,480
5Oct 21, 2026 02:321,7879,703,994715,000020,480
6Oct 21, 2026 02:321,79010,133,997716,000020,480
7Oct 21, 2026 02:321,7929,755,027717,000020,480
8Oct 21, 2026 02:321,7959,728,423718,000020,480
9Oct 21, 2026 02:321,7979,800,483719,000020,480