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 listMay 22, 2026 21:17M-RochatM-RochatError
Source Code

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

Challenge History

No challenges yet.

Run Statistics
#DateScoreWall TimeCPU UserCPU SystemMemoryError
1May 22, 2026 21:18015,842,3353,451,0001,094,0002,121,728expected "50", got "49 "
2May 22, 2026 21:18014,573,4383,471,0001,048,0002,121,728expected "64", got "50 "
3May 22, 2026 21:1811,22013,866,6273,407,0001,081,0002,121,728
4May 22, 2026 21:1811,28714,739,8893,434,0001,081,0002,121,728
5May 22, 2026 21:1811,31716,221,2543,436,0001,091,0002,121,728
6May 22, 2026 21:1811,40014,944,9693,377,0001,183,0002,121,728
7May 22, 2026 21:1811,51216,817,3253,555,0001,050,0002,121,728
8May 22, 2026 21:1811,53015,514,8213,560,0001,052,0002,121,728
9May 22, 2026 21:1811,66717,190,1453,610,0001,057,0002,121,728