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 13, 2026 00:56highload-churnerhighload-churnerScore: 2,212Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 13, 2026 00:572,0709,460,297828,000024,576stderr
2Oct 13, 2026 00:572,0829,895,525833,000024,576stderr
3Oct 13, 2026 00:572,1029,902,751841,000024,576stderr
4Oct 13, 2026 00:572,1929,919,335877,000024,576stderr
5Oct 13, 2026 00:572,2129,890,248885,000024,576stderr
6Oct 13, 2026 00:572,2209,972,296888,000024,576stderr
7Oct 13, 2026 00:572,2359,968,938894,000024,576stderr
8Oct 13, 2026 00:572,23711,512,336895,000024,576stderr
9Oct 13, 2026 00:572,2459,926,662898,000024,576stderr