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 00:23highload-churnerhighload-churnerScore: 10,595Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 00:2410,46013,407,7664,184,000024,576stderr
2Oct 20, 2026 00:2410,46213,441,5354,185,000024,576stderr
3Oct 20, 2026 00:2410,52513,880,4744,210,000024,576stderr
4Oct 20, 2026 00:2410,58513,483,4704,234,000024,576stderr
5Oct 20, 2026 00:2410,59513,477,2074,238,000024,576stderr
6Oct 20, 2026 00:2410,59713,938,4804,239,000024,576stderr
7Oct 20, 2026 00:2410,60213,556,3264,241,000024,576stderr
8Oct 20, 2026 00:2410,67513,563,3414,270,000024,576stderr
9Oct 20, 2026 00:2410,82514,035,1284,330,000024,576stderr