Factorial Function In C

#include "stdio.h"
#include "conio.h"
long int factorial(int n);
void main()
{
int n,i;
float s,r;
char c;
clrscr();
repeat : printf("You have this series:- 1/1! + 2/2! + 3/3! + 4/4!");
printf("To which term you want its sum? ");
scanf("%d",&n);
s=0;
for (i=1;i<=n;i++)
{
s=s+((float)i/(float)factorial(i));
}
printf("The sum of %d terms is %f",n,s);
fflush(stdin);
printf ("Do you want to continue?(y/n):- ");
scanf("%c",&c);
if (c=='y')
goto repeat;
getch();
}

long int factorial(int n)
{
if (n<=1)
return(1);
else
n=n*factorial(n-1);
return(n);
}