Armstrong Number between two

Giovanny Gongora

Find all Armstrong numbers between two integers entered by the user. In this program, we will print all the Armstrong numbers between two integers. This means that the two integers will not be part of the range, but only those integers that are between them.

#include <math.h>
#include <stdio.h>

int armstrongNumberInterval() {
  int low, high, number, originalNumber, rem, count = 0;
  double result = 0.0;
  printf("Enter two numbers(intervals): ");
  scanf("%d %d", &low, &high);
  printf("Armstrong numbers between %d and %d are: ", low, high);
  // swap numbers if high < low
  if (high < low) {
    high += low;
    low = high - low;
    high -= low;
  }
  // iterate number from (low + 1) to (high - 1)
  // In each iteration, check if number is Armstrong
  for (number = low + 1; number < high; ++number) {
    originalNumber = number;
    // number of digits calculation
    while (originalNumber != 0) {
      originalNumber /= 10;
      ++count;
    }
    originalNumber = number;
    // result contains sum of nth power of individual digits
    while (originalNumber != 0) {
      rem = originalNumber % 10;
      result += pow(rem, count);
      originalNumber /= 10;
    }
    // check if number is equal to the sum of nth power of individual digits
    if ((int)result == number) {
      printf("%d ", number);
    }
    // resetting the values
    count = 0;
    result = 0;
  }
  return 0;
}