c program to check armstrong number or not

#include <stdio.h>
 
int main()
{
   int r;

   long number = 0, c, sum = 0, temp;
 
   printf("Enter an integer upto which you want to find armstrong
   numbers\n");

   scanf("%ld",&number);
 
   printf("Following armstrong numbers are found from 1 to %ld\n",
   number);
 
   for( c = 1 ; c <= number ; c++ )
   {
      temp = c;

      while( temp != 0 )
      {
         r = temp%10;

         sum = sum + r*r*r;

         temp = temp/10;
      }

      if ( c == sum )

         printf("%ld\n", c);

      sum = 0;
   }
 
   return 0;
}