Program to find factorial of a number using recursion.

			#include<stdio.h>
			#include<conio.h>
			void main()
			{
			int n;
			clrscr();
			printf("enter number: ");
			scanf("%d",&n);
			if(n< 0)
			printf("invalid number");
			else
			printf("%d!=%d",n,fact(n));
			getch();
			}

			
			int fact(int x)
			{
			if(x==0)
			return 1;
			else
			return(x*fact(x-1));
			}
Output:
enter number: 5
5!=120