C Program to write the permutations of the characters of a string using Recursion

#include<stdio.h>
#include<string.h>
int main()
{
 void permute(char[],char[],int[],int,int);
 char A[100];
 scanf("%s",A);
 char B[100]="";
 int length=strlen(A);
 int level=0;
 int used[100]={0};
 permute(A,B,used,length,level);
 return 0;
}
void permute(char* A,char* B,int* used,int length,int level)
{
 if(level==length)
 {
  B[level]='';
  printf("%s\n",B);
  return;
 }
 else
 {
  for(int i=0;i<length;i++)
  {
   if(used[i]==1)
   {
    continue;
   }
   used[i]=1;
   B[level]=A[i];
   permute(A,B,used,length,level+1);
   used[i]=0;
   B[level]='';
  }
  return;
 }
}