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 04:41Karthik ReddyKarthik ReddyError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 3, 2026 04:4109,416,381725,000020,480expected "82", got "82 22 141 40 2 0 354 0 494 "
2Oct 3, 2026 04:4109,437,531784,000020,480expected "53", got "53 78 192 267 2 8 329 0 687 "
3Oct 3, 2026 04:4109,482,934766,000020,480expected "63", got "63 51 172 87 2 8 327 0 598 "