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 15:32highload-churnerhighload-churnerError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 19, 2026 15:3309,874,805719,000020,480expected "85", got "st49_tr99_mm142_ma60_fa171_gp23_50............. "
2Oct 19, 2026 15:33010,040,812718,000020,480expected "50", got "st45_tr93_mm137_ma60_fa163_gp23_50............. "
3Oct 19, 2026 15:3309,871,986879,000020,480expected "60", got "st44_tr102_mm97_ma60_fa160_gp22_50............. "