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 16, 2026 22:40Karthik ReddyKarthik ReddyScore: 1,940Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 16, 2026 22:421,7929,376,957717,000020,480
2Oct 16, 2026 22:421,8359,271,235734,000020,480
3Oct 16, 2026 22:421,8929,301,155757,000020,480
4Oct 16, 2026 22:421,9329,393,538773,000020,480
5Oct 16, 2026 22:421,9409,360,757776,000020,480
6Oct 16, 2026 22:421,9559,376,072782,000020,480
7Oct 16, 2026 22:421,9829,413,284793,000024,576
8Oct 16, 2026 22:422,15219,222,684861,000024,576
9Oct 16, 2026 22:422,16519,656,860866,000024,576