Program to generate permutation

Program:

#include<stdio.h>
#include<conio.h>
#include<string.h>
void main()
{
    int n, i, k = 0;
    char a[10];
    void perm(char a[10], int k, int n);
    clrscr();
    printf("Enter the string : ");
    scanf("%s", a);
    printf("\nThe permutation is :\n");
    n = strlen(a);
    perm(a, k, n);
    getch();
}
void perm(char a[10], int k, int n)
{
    char t, d[10];
    int i;
    if(k == n)
    {
        printf("\n%s", a);
        return;
    }
    else
    {
        for(i = k ; i < n ; i++)
        {
            t = a[i];
            a[i] = a[k];
            a[k] = t;
            strcpy(d, a);
            perm(d, k + 1, n);
        }
    }
}

Output:

Enter the string : abc
The permutation is :
abc
acb
bac
bca
cab
cba