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 11, 2026 08:02Victor MerckléVictor MerckléScore: 1,321,250Success
Source Code

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

Challenge History

No challenges yet.

Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jun 11, 2026 08:0316,84013,884,0476,736,00002,113,536
2Jun 11, 2026 08:0317,38014,113,0786,952,00002,113,536
3Jun 11, 2026 08:0317,87014,226,7206,015,0001,133,0002,113,536
4Jun 11, 2026 08:0318,11514,325,8227,246,00002,113,536
5Jun 11, 2026 08:031,321,250535,905,739514,476,00014,024,0002,113,536
6Jun 11, 2026 08:031,321,557535,875,205514,596,00014,027,0002,113,536
7Jun 11, 2026 08:031,322,042536,183,244514,793,00014,024,0002,113,536
8Jun 11, 2026 08:031,322,225536,205,417514,859,00014,031,0002,113,536
9Jun 11, 2026 08:031,323,110536,495,217515,208,00014,036,0002,113,536