Sample C# program to find the Permutation of a given string

The below C# program is used to print all the possible way to arrange the characters in the given string. Also known as Permutation.

Program :

using System;

public class Permutation
{
    public void Permute(string inputString, int startIndex, int endIndex)
    {
        if (startIndex == endIndex)
            Console.WriteLine(inputString);
        else
        {
            for (int i = startIndex; i <= endIndex; i++)
            {
                inputString = Swap(inputString, startIndex, i);
                Permute(inputString, startIndex + 1, endIndex);
                inputString = Swap(inputString, startIndex, i);
            }
        }
    }

    private string Swap(string a, int i, int j)
    {
        char temp;
        char[] arr = a.ToCharArray();
        temp = arr[i];
        arr[i] = arr[j];
        arr[j] = temp;

        return new string(arr);
    }
}

class Program
{
    static void Main(string[] args)
    {
        string inputString = "ABC";
        Permutation p = new Permutation();
        p.Permute(inputString, 0, inputString.Length - 1);

        Console.ReadLine();
    }
}

Output :

ABC
ACB
BAC
BCA
CBA
CAB