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 9, 2026 08:15Karthik ReddyKarthik ReddyError
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 9, 2026 09:0709,364,006733,000020,480expected "65", got "50 "
2Oct 9, 2026 09:071,7229,940,186689,000020,480
3Oct 9, 2026 09:071,7729,234,162709,000020,480
4Oct 9, 2026 09:071,7829,352,271713,000020,480
5Oct 9, 2026 09:071,8009,320,179720,000020,480
6Oct 9, 2026 09:071,8229,203,823729,000020,480
7Oct 9, 2026 09:071,8229,401,297729,000020,480
8Oct 9, 2026 09:071,8329,497,305733,000020,480
9Oct 9, 2026 09:071,8559,403,994742,000020,480