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 18:26Kevin HeaveyKevin HeaveyScore: 1,830Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Sep 26, 2026 18:271,8229,162,301729,000020,480
2Sep 26, 2026 18:271,8229,138,093729,000020,480
3Sep 26, 2026 18:271,8259,220,134730,000020,480
4Sep 26, 2026 18:271,8259,332,444730,000020,480
5Sep 26, 2026 18:271,8309,203,187732,000020,480
6Sep 26, 2026 18:271,83010,900,071732,000020,480
7Sep 26, 2026 18:271,8329,175,004733,000020,480
8Sep 26, 2026 18:271,8579,247,528743,000020,480
9Sep 26, 2026 18:271,8579,196,640743,000020,480