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 03:05highload-churnerhighload-churnerScore: 1,812Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 03:061,72510,050,828690,000020,480
2Oct 20, 2026 03:061,7979,713,590719,000020,480
3Oct 20, 2026 03:061,80510,754,808722,000020,480
4Oct 20, 2026 03:061,80710,043,832723,000020,480
5Oct 20, 2026 03:061,8129,629,063725,000020,480
6Oct 20, 2026 03:061,8159,636,496726,000020,480
7Oct 20, 2026 03:061,84210,026,036737,000020,480
8Oct 20, 2026 03:061,85010,141,770740,000020,480
9Oct 20, 2026 03:062,02710,227,579811,000020,480