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 04:54Karthik ReddyKarthik ReddyError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 3, 2026 04:5509,908,483724,000020,480expected "72", got "72 5 138 25 1 0 351 0 465 22 417 35 "
2Oct 3, 2026 04:55010,585,814804,000020,480expected "50", got "50 89 196 569 1 8 321 0 783 17 665 46 "
3Oct 3, 2026 04:5509,259,781791,000020,480expected "86", got "86 99 194 62 2 0 323 0 660 27 589 56 "