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 04:36Karthik ReddyKarthik ReddyError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 3, 2026 04:3709,271,621780,000020,480expected "58", got "58 26 175 303 2 280 370 0 649 "
2Oct 3, 2026 04:3709,448,230824,000020,480expected "58", got "58 57 185 654 2 530 326 0 767 "
3Oct 3, 2026 04:3709,514,834858,000020,480expected "86", got "86 79 194 912 2 779 326 0 933 "