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 3, 2026 04:24Karthik ReddyKarthik ReddyError
Source Code

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

Challenge History

No challenges yet.

Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Oct 3, 2026 04:2509,510,305834,000020,480expected "50", got "50 119 1104 2 14 79 182 361 589 295 "
2Oct 3, 2026 04:2509,519,359828,000020,480expected "50", got "50 111 1039 1 14 76 169 352 585 246 "
3Oct 3, 2026 04:2509,539,136838,000020,480expected "50", got "50 102 909 1 14 88 154 337 607 244 "