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 07:13highload-churnerhighload-churnerScore: 1,772Success
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 07:141,58010,010,611632,000020,480
2Oct 20, 2026 07:141,74710,060,025699,000020,480
3Oct 20, 2026 07:141,75510,103,661702,000020,480
4Oct 20, 2026 07:141,7629,959,576705,000020,480
5Oct 20, 2026 07:141,77210,010,020709,000020,480
6Oct 20, 2026 07:141,77710,042,641711,000020,480
7Oct 20, 2026 07:141,79710,018,777719,000020,480
8Oct 20, 2026 07:141,79710,001,058719,000020,480
9Oct 20, 2026 07:142,14210,166,137857,000020,480