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 18:33Andrew EpsteinAndrew EpsteinScore: 1,990Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Sep 13, 2026 18:351,9079,079,250763,000020,480
2Sep 13, 2026 18:351,9129,787,583765,000020,480
3Sep 13, 2026 18:351,9229,818,614769,000020,480
4Sep 13, 2026 18:351,9629,857,025785,000020,480
5Sep 13, 2026 18:351,9909,308,355796,000020,480
6Sep 13, 2026 18:351,9929,847,230797,000020,480
7Sep 13, 2026 18:352,0059,107,297802,000020,480
8Sep 13, 2026 18:352,2809,404,922912,000020,480
9Sep 13, 2026 18:352,3629,953,561945,000020,480