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 12, 2026 17:09highload-churnerhighload-churnerScore: 4,585Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 12, 2026 17:104,48011,051,2911,792,000024,576stderr
2Oct 12, 2026 17:104,50211,115,7621,801,000024,576stderr
3Oct 12, 2026 17:104,53511,089,7441,814,000024,576stderr
4Oct 12, 2026 17:104,57010,791,6611,828,000024,576stderr
5Oct 12, 2026 17:104,58510,618,7491,834,000024,576stderr
6Oct 12, 2026 17:104,59710,634,0491,839,000024,576stderr
7Oct 12, 2026 17:104,63010,698,2901,852,000024,576stderr
8Oct 12, 2026 17:104,63211,151,0481,853,000024,576stderr
9Oct 12, 2026 17:104,99711,322,9831,999,000024,576stderr