C programming using Recursion concept.

#include<stdio.h>
int main()
{
  int factorial(int x);
  int a,Ans;
  printf("\n Enter a number of which factorial you want to calculate:");
  scanf("%d",&a);
  Ans=factorial(a);
  printf("\n The factorial of %d is=%d",a,Ans);
  return 0;
}
int factorial(int x)
{
  int f;
  if(x<=1)
{  
   return 1;
}
  f= x * factorial(x-1);
  return (f);
}