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 18:36highload-churnerhighload-churnerScore: 2,580Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 9, 2026 18:372,2329,476,506893,000024,576
2Oct 9, 2026 18:372,4729,583,410989,000024,576
3Oct 9, 2026 18:372,4809,594,736992,000024,576
4Oct 9, 2026 18:372,5209,729,6711,008,000024,576
5Oct 9, 2026 18:372,5809,688,2241,032,000024,576
6Oct 9, 2026 18:372,60511,173,0141,042,000024,576
7Oct 9, 2026 18:372,6129,735,6381,045,000024,576
8Oct 9, 2026 18:372,6179,634,0421,047,000024,576
9Oct 9, 2026 18:372,6779,570,5041,071,000024,576