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 21, 2026 01:44highload-churnerhighload-churnerScore: 1,822Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 21, 2026 01:451,6829,609,079673,000024,576stderr
2Oct 21, 2026 01:451,8009,681,909720,000024,576stderr
3Oct 21, 2026 01:451,8029,579,595721,000024,576stderr
4Oct 21, 2026 01:451,8229,732,545729,000024,576stderr
5Oct 21, 2026 01:451,82210,062,267729,000024,576stderr
6Oct 21, 2026 01:451,85010,097,429740,000024,576stderr
7Oct 21, 2026 01:451,85210,103,290741,000024,576stderr
8Oct 21, 2026 01:451,86710,075,506747,000024,576stderr
9Oct 21, 2026 01:452,04210,183,317817,000024,576stderr