factorial of a given number using function

#include<iostream>
using namespace std;
int fact(int );
void main()

{
int n,i,c;
cout<<"Enter the number";
cin>>n;
c=fact(n);
cout<<"\nfactorial="<<c;
system("PAUSE");
}
int fact(int n)
{
int i,fac=1;
for(i=n;i>0;i--)
{
fac=fac*i;
}
return fac;
}