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 3, 2026 04:13Karthik ReddyKarthik ReddyError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 3, 2026 04:1409,199,161633,00002,113,536expected "80", got "50 "
2Oct 3, 2026 04:1409,316,515737,00002,113,536expected "63", got "50 "
3Oct 3, 2026 04:1409,231,147640,00002,113,536expected "84", got "50 "
4Oct 3, 2026 04:1409,024,378640,00002,113,536expected "55", got "50 "
5Oct 3, 2026 04:1409,298,057640,00002,113,536expected "56", got "50 "
6Oct 3, 2026 04:141,5859,232,413634,00002,113,536
7Oct 3, 2026 04:141,5859,275,557634,00002,113,536
8Oct 3, 2026 04:141,6129,246,057645,00002,113,536
9Oct 3, 2026 04:141,8509,645,057740,00002,113,536