Largest Square Submatrix of all 1's NoSIMD_C#

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 listJun 17, 2026 04:02Victor MerckléVictor MerckléError
Source Code

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

Challenge History

No challenges yet.

Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jun 17, 2026 04:0408,930,0591,737,00002,113,536expected "58", got "50 "
2Jun 17, 2026 04:041,8457,890,821738,00002,113,536
3Jun 17, 2026 04:042,3808,024,631952,00002,113,536
4Jun 17, 2026 04:042,5628,081,0031,025,00002,113,536
5Jun 17, 2026 04:042,7878,254,3651,115,00002,113,536
6Jun 17, 2026 04:042,9608,352,9981,184,00002,113,536
7Jun 17, 2026 04:042,9908,342,0901,196,00002,113,536
8Jun 17, 2026 04:043,9828,758,8071,593,00002,113,536
9Jun 17, 2026 04:044,0958,788,2001,638,00002,113,536