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 10, 2026 00:16highload-churnerhighload-churnerScore: 2,432Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 10, 2026 01:492,2109,568,191884,000024,576
2Oct 10, 2026 01:492,2559,574,442902,000024,576
3Oct 10, 2026 01:492,3809,646,327952,000024,576
4Oct 10, 2026 01:492,4309,678,186972,000024,576
5Oct 10, 2026 01:492,4329,725,200973,000024,576
6Oct 10, 2026 01:492,4379,673,831975,000024,576
7Oct 10, 2026 01:492,4509,790,329980,000024,576
8Oct 10, 2026 01:492,4659,737,006986,000024,576
9Oct 10, 2026 01:492,49210,420,449997,000024,576