NCR and NPR in C

#include<stdio.h>

long factorial(int);
long find_ncr(int, int);
long find_npr(int, int);

main()
{
   int n, r;
   long ncr, npr;

   printf("Enter the value of n and r\n");
   scanf("%d%d",&n,&r);

   ncr = find_ncr(n, r);
   npr = find_npr(n, r);

   printf("%dC%d = %ld\n", n, r, ncr);
   printf("%dP%d = %ld\n", n, r, npr);

   return 0;
}

long find_ncr(int n, int r)
{
   long result;

   result = factorial(n)/(factorial(r)*factorial(n-r));

   return result;
}

long find_npr(int n, int r)
{
   long result;

   result = factorial(n)/factorial(n-r);

   return result;
}

long factorial(int n)
{
   int c;
   long result = 1;

   for( c = 1 ; c <= n ; c++ )
      result = result*c;

   return ( result );
}