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 09:45highload-churnerhighload-churnerScore: 1,787Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 09:461,6509,716,604660,000020,480
2Oct 20, 2026 09:461,6909,712,639676,000020,480
3Oct 20, 2026 09:461,78010,134,191712,000020,480
4Oct 20, 2026 09:461,78510,132,457714,000020,480
5Oct 20, 2026 09:461,7879,810,443715,000020,480
6Oct 20, 2026 09:461,7929,833,612717,000020,480
7Oct 20, 2026 09:461,8009,751,356720,000020,480
8Oct 20, 2026 09:461,81210,238,457725,000020,480
9Oct 20, 2026 09:461,8159,738,872726,000020,480