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 00:35highload-churnerhighload-churnerScore: 1,770Success
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 00:361,64211,423,408657,000020,480
2Oct 20, 2026 00:361,6579,968,834663,000020,480
3Oct 20, 2026 00:361,6779,963,697671,000020,480
4Oct 20, 2026 00:361,7679,653,874707,000020,480
5Oct 20, 2026 00:361,77010,090,657708,000020,480
6Oct 20, 2026 00:361,79010,067,683716,000020,480
7Oct 20, 2026 00:361,8159,608,411726,000020,480
8Oct 20, 2026 00:361,8229,664,946729,000020,480
9Oct 20, 2026 00:361,8579,564,837743,000020,480