Factorial of number in C.

1:  #include <stdio.h>  
2:  long factorial(int n)  
3:  {  
4:    if(n ==0)  
5:    {  
6:      return 1;  
7:    }  
8:    return (n * factorial(n-1));  
9:  }  
10:  main()  
11:  {  
12:    int n;  
13:    long fact = 0;  
14:    printf("Enter a Number : ");  
15:    scanf("%d",&n);  
16:    fact = factorial(n);  
17:    printf("Result = %ld\n",fact);  
18:  }