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 01:14highload-churnerhighload-churnerScore: 2,947Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 01:152,89510,220,1971,158,000024,576stderr
2Oct 20, 2026 01:152,91710,196,1101,167,000024,576stderr
3Oct 20, 2026 01:152,92510,712,4181,170,000024,576stderr
4Oct 20, 2026 01:152,93010,634,9341,172,000024,576stderr
5Oct 20, 2026 01:152,94710,754,2011,179,000024,576stderr
6Oct 20, 2026 01:152,95710,472,7231,183,000024,576stderr
7Oct 20, 2026 01:152,98010,706,8191,192,000024,576stderr
8Oct 20, 2026 01:153,10710,343,7901,243,000024,576stderr
9Oct 20, 2026 01:153,34710,425,8311,339,000024,576stderr