#include<stdio.h>

#include<conio.h>

long factorial(int n) // function to calculate the factorial of a given number.

{

if (n == 0)

return 1;

else

return(n * factorial(n-1)); //calling the function recursively.

}

void main()

{

int number; //declaration of variables.

long fact;

clrscr();

printf(“Enter a number: “);

scanf(“%d”, &number);

fact = factorial(number); //calling a function.

printf(“Factorial of %d is %ld\n”, number, fact);

getch(); //It reads a character from the keyword.

}