Program to Generate Permutation of String in C | C Program

Here's a C program to generate permutations of a string with output. This program makes use of C concepts like Array, For loop,  IF-Else Condition, Recursion and String Functions like string copy (strcpy()) and string length (strlen()) functions etc.

# 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 of above program

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