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 23:43highload-churnerhighload-churnerScore: 2,415Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 10, 2026 01:262,2329,588,050893,000024,576
2Oct 10, 2026 01:262,3159,625,589926,000024,576
3Oct 10, 2026 01:262,3809,643,658952,000024,576
4Oct 10, 2026 01:262,3909,669,741956,000024,576
5Oct 10, 2026 01:262,4159,589,149966,000024,576
6Oct 10, 2026 01:262,41510,179,965966,000024,576
7Oct 10, 2026 01:262,4259,583,643970,000024,576
8Oct 10, 2026 01:262,4779,667,259991,000024,576
9Oct 10, 2026 01:262,4829,683,773993,000024,576