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 19, 2026 15:19highload-churnerhighload-churnerError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 19, 2026 15:19010,064,650735,000020,480expected "50", got "409_466_655_50 "
2Oct 19, 2026 15:19010,105,909745,000020,480expected "50", got "417_468_662_50 "
3Oct 19, 2026 15:19010,002,689682,000020,480expected "83", got "411_462_599_83 "