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 listNov 6, 2026 05:31Andrew EpsteinAndrew EpsteinScore: 2,262Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Nov 6, 2026 05:331,7079,609,050683,000020,480
2Nov 6, 2026 05:331,7259,709,249690,000020,480
3Nov 6, 2026 05:331,7409,694,029696,000020,480
4Nov 6, 2026 05:331,74710,090,347699,000020,480
5Nov 6, 2026 05:332,2629,870,792905,000020,480
6Nov 6, 2026 05:332,2959,962,003918,000020,480
7Nov 6, 2026 05:332,3129,981,547925,000020,480
8Nov 6, 2026 05:332,38010,004,867952,000020,480
9Nov 6, 2026 05:332,69710,479,6721,079,000020,480