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 19:32Kevin HeaveyKevin HeaveyScore: 1,967Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Sep 26, 2026 19:381,89011,930,999756,000020,480
2Sep 26, 2026 19:381,93711,581,340775,000020,480
3Sep 26, 2026 19:381,96711,307,083787,000020,480
4Sep 26, 2026 19:381,96711,443,491787,000020,480
5Sep 26, 2026 19:381,96711,501,006787,000020,480
6Sep 26, 2026 19:381,97011,088,599788,000020,480
7Sep 26, 2026 19:381,97210,577,093789,000020,480
8Sep 26, 2026 19:381,98710,679,800795,000020,480
9Sep 26, 2026 19:382,00711,024,658803,000020,480