armstrong.c

#include "stdlib.h"
#include "stdio.h"
#include "math.h"

int main()
{
  int num, temp;
  int digits;
  int i;
  long sum;

  scanf( "%d", &num);

  temp = num;
  digits = 0;
  while( temp)
  {
    temp /= 10;
    digits++;
  }

  temp = num;
  sum = 0;
  for( i = 0; i < digits; i++)
  {
    sum += pow( temp % 10, digits);
    temp /= 10;
  }

  if( sum == num)
    printf( "%d is an armstrong number\n", num);
  else
    printf( "%d is not an armstrong number\n", num);
  
  return 0;
}