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 12:47highload-churnerhighload-churnerScore: 2,167Success
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 12:492,0779,854,501831,000024,576stderr
2Oct 19, 2026 12:492,11510,265,352846,000024,576stderr
3Oct 19, 2026 12:492,14710,206,711859,000024,576stderr
4Oct 19, 2026 12:492,16510,213,167866,000024,576stderr
5Oct 19, 2026 12:492,1679,902,183867,000024,576stderr
6Oct 19, 2026 12:492,17210,217,797869,000024,576stderr
7Oct 19, 2026 12:492,1829,920,437873,000024,576stderr
8Oct 19, 2026 12:492,20010,269,236880,000024,576stderr
9Oct 19, 2026 12:492,24710,261,592899,000024,576stderr