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 16, 2026 12:20Victor MerckléVictor MerckléScore: 72,147Success
Source Code

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

Challenge History

No challenges yet.

Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1Jun 16, 2026 12:221,8177,881,883727,00002,113,536
2Jun 16, 2026 12:222,4208,026,130968,00002,113,536
3Jun 16, 2026 12:2255,15729,252,08122,063,00002,113,536
4Jun 16, 2026 12:2258,22530,290,37223,290,00002,113,536
5Jun 16, 2026 12:2272,14736,052,22528,859,00002,113,536
6Jun 16, 2026 12:2278,14238,561,91031,257,00002,113,536
7Jun 16, 2026 12:2280,87539,357,19232,350,00002,113,536
8Jun 16, 2026 12:2283,02740,402,08733,211,00002,113,536
9Jun 16, 2026 12:2296,11745,750,77438,447,00002,113,536