Printing Pascal triangle using C

#include <stdio.h>

long factorial(int);
main()
{
   int i, n, c;
   printf("Enter the number of rows you wish to see in pascal triangle\n");
   scanf("%d",&n);

   for ( i = 0 ; i < n ; i++ )
   {
      for ( c = 0 ; c <= ( n - i - 2 ) ; c++ )
         printf(" ");

      for( c = 0 ; c <= i ; c++ )
         printf("%ld ",factorial(i)/(factorial(c)*factorial(i-c)));

      printf("\n");
   }
}

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

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

   return ( result );
}