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 21, 2026 01:39highload-churnerhighload-churnerScore: 7,400Success
Source Code

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

Challenge History

No challenges yet.

Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 21, 2026 01:406,53512,418,3502,614,000024,576stderr
2Oct 21, 2026 01:407,02712,043,1482,811,000024,576stderr
3Oct 21, 2026 01:407,03012,553,5752,812,000024,576stderr
4Oct 21, 2026 01:407,19512,625,1422,878,000024,576stderr
5Oct 21, 2026 01:407,40012,604,0562,960,000024,576stderr
6Oct 21, 2026 01:407,64714,786,7473,059,000024,576stderr
7Oct 21, 2026 01:407,66212,735,4473,065,000024,576stderr
8Oct 21, 2026 01:407,66512,737,5553,066,000024,576stderr
9Oct 21, 2026 01:407,82012,508,9423,128,000024,576stderr