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 listSep 26, 2026 22:08Kevin HeaveyKevin HeaveyScore: 1,960Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Sep 26, 2026 22:101,90510,486,622762,000020,480
2Sep 26, 2026 22:101,9309,472,280772,000020,480
3Sep 26, 2026 22:101,93511,410,555774,000020,480
4Sep 26, 2026 22:101,95011,598,266780,000020,480
5Sep 26, 2026 22:101,96011,293,657784,000020,480
6Sep 26, 2026 22:101,96212,802,300785,000020,480
7Sep 26, 2026 22:101,98011,634,983792,000020,480
8Sep 26, 2026 22:102,28511,573,120914,000020,480
9Sep 26, 2026 22:102,37511,270,027950,000020,480