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 13, 2026 21:02Andrew EpsteinAndrew EpsteinScore: 1,942Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Sep 13, 2026 21:051,8628,918,165745,000020,480
2Sep 13, 2026 21:051,8808,951,538752,000020,480
3Sep 13, 2026 21:051,9078,939,746763,000020,480
4Sep 13, 2026 21:051,9359,036,849774,000020,480
5Sep 13, 2026 21:051,9429,055,286777,000020,480
6Sep 13, 2026 21:051,98517,321,820794,000020,480
7Sep 13, 2026 21:051,9978,869,695799,000020,480
8Sep 13, 2026 21:052,02217,405,482809,000020,480
9Sep 13, 2026 21:052,3529,120,025941,000020,480