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 08:18highload-churnerhighload-churnerScore: 1,765Success
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Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 08:201,6009,933,937640,000020,480
2Oct 20, 2026 08:201,6459,635,445658,000020,480
3Oct 20, 2026 08:201,73010,023,846692,000020,480
4Oct 20, 2026 08:201,7629,964,823705,000020,480
5Oct 20, 2026 08:201,7659,704,146706,000020,480
6Oct 20, 2026 08:201,7779,746,486711,000020,480
7Oct 20, 2026 08:201,80710,017,797723,000020,480
8Oct 20, 2026 08:201,81210,000,269725,000020,480
9Oct 20, 2026 08:201,81210,016,016725,000020,480