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 04:27highload-churnerhighload-churnerScore: 1,790Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 04:281,65211,066,388661,000020,480
2Oct 20, 2026 04:281,6929,633,235677,000020,480
3Oct 20, 2026 04:281,7659,568,391706,000020,480
4Oct 20, 2026 04:281,77210,035,465709,000020,480
5Oct 20, 2026 04:281,79010,063,316716,000020,480
6Oct 20, 2026 04:281,7929,636,325717,000020,480
7Oct 20, 2026 04:281,81210,017,259725,000020,480
8Oct 20, 2026 04:281,82210,153,534729,000020,480
9Oct 20, 2026 04:282,05010,183,565820,000020,480