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 06:58highload-churnerhighload-churnerScore: 1,782Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 06:591,6929,747,464677,000020,480
2Oct 20, 2026 06:591,7059,986,272682,000020,480
3Oct 20, 2026 06:591,74210,050,215697,000020,480
4Oct 20, 2026 06:591,76510,010,172706,000020,480
5Oct 20, 2026 06:591,7829,698,550713,000020,480
6Oct 20, 2026 06:591,80710,094,274723,000020,480
7Oct 20, 2026 06:591,80711,550,617723,000020,480
8Oct 20, 2026 06:591,8159,663,558726,000020,480
9Oct 20, 2026 06:591,81510,063,107726,000020,480