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 01:29highload-churnerhighload-churnerScore: 1,775Success
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 01:301,6709,981,236668,000020,480
2Oct 20, 2026 01:301,72010,000,732688,000020,480
3Oct 20, 2026 01:301,74010,039,386696,000020,480
4Oct 20, 2026 01:301,77210,023,736709,000020,480
5Oct 20, 2026 01:301,77510,055,450710,000020,480
6Oct 20, 2026 01:301,7859,702,594714,000020,480
7Oct 20, 2026 01:301,7959,759,886718,000020,480
8Oct 20, 2026 01:301,7979,602,688719,000020,480
9Oct 20, 2026 01:302,0429,783,997817,000020,480