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 19, 2026 14:51highload-churnerhighload-churnerScore: 7,297Success
Source Code

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

Challenge History

No challenges yet.

Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 19, 2026 14:527,13012,081,2772,852,00002,117,632stderr
2Oct 19, 2026 14:527,22712,250,2822,891,00002,117,632stderr
3Oct 19, 2026 14:527,24012,574,0332,896,00002,117,632stderr
4Oct 19, 2026 14:527,27512,579,7722,910,00002,117,632stderr
5Oct 19, 2026 14:527,29712,627,1282,919,00002,117,632stderr
6Oct 19, 2026 14:527,35012,660,7682,940,00002,117,632stderr
7Oct 19, 2026 14:527,35212,677,1612,941,00002,117,632stderr
8Oct 19, 2026 14:527,48212,219,2072,993,00002,117,632stderr
9Oct 19, 2026 14:527,50523,730,0303,002,00002,117,632stderr