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 10:10highload-churnerhighload-churnerScore: 1,760Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 10:111,69510,031,092678,000020,480
2Oct 20, 2026 10:111,7359,740,837694,000020,480
3Oct 20, 2026 10:111,7379,725,094695,000020,480
4Oct 20, 2026 10:111,75010,113,896700,000020,480
5Oct 20, 2026 10:111,76010,107,921704,000020,480
6Oct 20, 2026 10:111,76710,047,919707,000020,480
7Oct 20, 2026 10:111,77010,150,620708,000020,480
8Oct 20, 2026 10:111,79510,176,699718,000020,480
9Oct 20, 2026 10:111,7979,756,427719,000020,480