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 05:56Karthik ReddyKarthik ReddyError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 3, 2026 05:560490,939,612456,461,00023,145,0002,113,536expected "68", got "A68 h18,18,10,27,18,23,19,24,19,24,10 big1 68@353,9612 "
2Oct 3, 2026 05:560489,301,111456,171,00022,587,0002,113,536expected "50", got "A50 h21,20,23,17,24,22,21,24,12,14,25 big0 "
3Oct 3, 2026 05:560496,377,100455,382,00022,775,0002,113,536expected "50", got "A50 h16,15,16,17,10,15,15,20,17,20,27 big0 "