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 09:17highload-churnerhighload-churnerScore: 1,805Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 09:191,76510,052,707706,000020,480
2Oct 20, 2026 09:191,76710,011,765707,000020,480
3Oct 20, 2026 09:191,7679,670,599707,000020,480
4Oct 20, 2026 09:191,8029,722,750721,000020,480
5Oct 20, 2026 09:191,80510,067,628722,000020,480
6Oct 20, 2026 09:191,8059,992,596722,000020,480
7Oct 20, 2026 09:191,8209,998,348728,000020,480
8Oct 20, 2026 09:191,82210,038,114729,000020,480
9Oct 20, 2026 09:191,91210,103,924765,000020,480