#include <stdio.h>
#include <string.h>
void swap(char *x, char *y)
{
	char temp;
	temp = *x;
	*x = *y;
	*y = temp;
}
void permute(char *a, int l, int r)
{
int i;
if (l == r)
	printf("%s\n", a);
else
{
	for (i = l; i <= r; i++)
	{
		swap((a+l), (a+i));
		permute(a, l+1, r);
		swap((a+l), (a+i)); 
    }
}
}
int main()
{
	char str[100];
   scanf("%s",str);
	int n = strlen(str);
	permute(str, 0, n-1);
	return 0;
}

• Problem Description
  Given alphabets i,j .Write a C Program to Generate All Permutations of the given alphabets using BackTracking.
• Test Case 1
  Input (stdin)ij
  Expected Outputij
  ji
• Test Case 2
  Input (stdin)iiij
  Expected Outputiiij
  iiji
  iiij
  iiji
  ijii
  ijii
  iiij
  iiji
  iiij
  iiji
  ijii
  ijii
  iiij
  iiji
  iiij
  iiji
  ijii
  ijii
  jiii
  jiii
  jiii
  jiii
  jiii
  jiii