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 01:21highload-churnerhighload-churnerScore: 2,890Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 01:222,81710,358,4591,127,000024,576stderr
2Oct 20, 2026 01:222,82510,636,4921,130,000024,576stderr
3Oct 20, 2026 01:222,83512,147,8531,134,000024,576stderr
4Oct 20, 2026 01:222,85010,622,1781,140,000024,576stderr
5Oct 20, 2026 01:222,89010,568,9001,156,000024,576stderr
6Oct 20, 2026 01:222,90510,655,6581,162,000024,576stderr
7Oct 20, 2026 01:222,92210,453,9191,169,000024,576stderr
8Oct 20, 2026 01:222,93710,272,9871,175,000024,576stderr
9Oct 20, 2026 01:222,94010,261,2751,176,000024,576stderr