C# - How to show every combination of a 3 decimal placed number (4 numbers outside of the decimals)

Question

I am wondering how to write all the possible combinations of a number with 3 decimals in it.

As you might have guessed I am using this for IP addresses, so I need the numbers for the 4 decimal places to be between 0 and 255. Is there any way I can write in a console application every combination of a 4 decimal place number (0.0.0.0 - 255.255.255.255)? If this can be done, a reply would be awesome. Thanks for reading!

Everything in the world is doable if we try. So go ahead and give it a try, post your efforts here, and then come up with specific issue. — Nikhil Vartak, May 13 '17 at 21:40
Thanks for the reply. I was messing around with this project for awhile, but didn't know what code sample to post here because I was unsure what could be relevant to the question. — Jkaay, May 13 '17 at 21:42

score 1 · Accepted Answer · answered May 13 '17 at 21:42

1

Yes, you can achieve this with simple nested for loops like this:

public class Program
{
    public static void Main(string[] args)
    {
        for (int a = 0; a < 256; a++)
        {
           for (int b = 0; b < 256; b++)
           {
               for (int c = 0; c < 256; c++) 
               {
                   for (int d = 0; d < 256; d++)
                   {
                       string ipAddress = string.Format("{0}.{1}.{2}.{3}", a, b, c, d);
                       Console.WriteLine(ipAddress);
                   }
               }
           }
        }
    }
}

answered May 13 '17 at 21:42

xcvd

666
1
5
13

Thanks, works perfectly! Appreciate the fast response. – Jkaay May 13 '17 at 21:46
1

@TamásSzabó Your edit doesn´t make this answer even any more readable, it´s quite okay as it is. – HimBromBeere May 13 '17 at 21:55
@HimBromBeere Alright, I guess it's just personal opinion then. – Tamás Szabó May 13 '17 at 21:57
@HimBromBeere Just out of curiosity, are you against using `using` blocks the same fashion too? – Tamás Szabó May 13 '17 at 21:58
@TamásSzabó I don´t have anything against this style, my comment was just related to your edit which didn´t introduced any improvement - but no harm however. – HimBromBeere May 14 '17 at 00:13

score 0 · Answer 2 · edited May 23 '17 at 12:34

0

Since you can convert an IP4 address to integer, you could do this in one for loop:

for (uint i = 0; i <= 4294967295; i++)
{
    byte[] bytes = BitConverter.GetBytes(i);
    Array.Reverse(bytes);
    string ipAddress = new IPAddress(bytes).ToString();
    Console.WriteLine(ipAddress);
}

edited May 23 '17 at 12:34

Community

1
1

answered May 13 '17 at 22:08

Filburt

16,221
12
59
107

C# - How to show every combination of a 3 decimal placed number (4 numbers outside of the decimals)

2 Answers2