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 20, 2026 01:48highload-churnerhighload-churnerScore: 5,745Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 01:505,29211,837,1092,117,000024,576stderr
2Oct 20, 2026 01:505,51711,467,4842,207,000024,576stderr
3Oct 20, 2026 01:505,60213,632,4072,241,000024,576stderr
4Oct 20, 2026 01:505,69212,036,4792,277,000024,576stderr
5Oct 20, 2026 01:505,74511,581,6492,298,000024,576stderr
6Oct 20, 2026 01:505,76011,466,4922,304,000024,576stderr
7Oct 20, 2026 01:505,78211,618,5962,313,000024,576stderr
8Oct 20, 2026 01:505,81512,078,1262,326,000024,576stderr
9Oct 20, 2026 01:506,01212,427,8592,405,000024,576stderr