Program to generate permutation Using C

# 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) ;
}
}
}

RUN 1 :
~~~~~~~
Enter the string : abc
The permutation is :
abc
acb
bac
bca
cab
cba