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 05:31highload-churnerhighload-churnerScore: 2,915Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 05:322,85010,223,8311,140,000024,576stderr
2Oct 20, 2026 05:322,89010,614,6211,156,000024,576stderr
3Oct 20, 2026 05:322,90210,251,0761,161,000024,576stderr
4Oct 20, 2026 05:322,91210,180,8221,165,000024,576stderr
5Oct 20, 2026 05:322,91510,641,4231,166,000024,576stderr
6Oct 20, 2026 05:322,91710,683,5861,167,000024,576stderr
7Oct 20, 2026 05:322,92710,674,7281,171,000024,576stderr
8Oct 20, 2026 05:322,93510,378,8641,174,000024,576stderr
9Oct 20, 2026 05:323,06210,281,7301,225,000024,576stderr