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 listOct 20, 2026 02:16highload-churnerhighload-churnerScore: 5,565Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 02:175,06011,721,1562,024,000024,576stderr
2Oct 20, 2026 02:175,28211,328,3222,113,000024,576stderr
3Oct 20, 2026 02:175,34511,874,2532,138,000024,576stderr
4Oct 20, 2026 02:175,48711,352,5282,195,000024,576stderr
5Oct 20, 2026 02:175,56511,471,7732,226,000024,576stderr
6Oct 20, 2026 02:175,59211,540,4572,237,000024,576stderr
7Oct 20, 2026 02:175,60011,446,3172,240,000024,576stderr
8Oct 20, 2026 02:175,63512,024,9452,254,000024,576stderr
9Oct 20, 2026 02:175,83212,080,7762,333,000024,576stderr