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 08:04highload-churnerhighload-churnerScore: 1,765Success
Source Code

Source code access is restricted. Log in to request access.

Challenge History

No challenges yet.

Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 20, 2026 08:061,6329,723,027653,000020,480
2Oct 20, 2026 08:061,6359,735,263654,000020,480
3Oct 20, 2026 08:061,74210,060,745697,000020,480
4Oct 20, 2026 08:061,7579,774,170703,000020,480
5Oct 20, 2026 08:061,7659,798,533706,000020,480
6Oct 20, 2026 08:061,76710,143,440707,000020,480
7Oct 20, 2026 08:061,77210,020,954709,000020,480
8Oct 20, 2026 08:061,7859,723,440714,000020,480
9Oct 20, 2026 08:062,0679,819,969827,000020,480