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 08:06highload-churnerhighload-churnerScore: 9,350Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 08:079,28013,379,8403,712,000024,576stderr
2Oct 20, 2026 08:079,30712,966,3393,723,000024,576stderr
3Oct 20, 2026 08:079,31212,948,3523,725,000024,576stderr
4Oct 20, 2026 08:079,32712,953,1443,731,000024,576stderr
5Oct 20, 2026 08:079,35013,427,9133,740,000024,576stderr
6Oct 20, 2026 08:079,35513,421,7823,742,000024,576stderr
7Oct 20, 2026 08:079,36713,437,2693,747,000024,576stderr
8Oct 20, 2026 08:079,37213,429,7983,749,000024,576stderr
9Oct 20, 2026 08:079,38213,422,6073,753,000024,576stderr