C++ Programing Example to Display Armstrong Number Between Two Intervals-DevsEnv

#1 Code Example- C++ Program Display Armstrong Number Between Intervals

Code - C++ Programming

#include <iostream>
#include <cmath>
using namespace std;

int main() {

  int num1, num2, i, num, digit, sum, count;

  cout << "Enter first number: ";
  cin >> num1;

  cout << "Enter second number: ";
  cin >> num2;

  // swap if num1 > num2
  if (num1 > num2) {
    num1 = num1 + num2;
    num2 = num1 - num2;
    num1 = num1 - num2;
  }
  
  cout << "Armstrong numbers between " << num1 << " and " << num2 << " are: " <<endl;
 
  // print Armstrong numbers from num1 to num2
  for(i = num1; i <= num2; i++) {

    // count gives the number of digits in i
    count = 0;
         
    // store value of i in num
    num = i;

    // count the number of digits in num and i
    while(num > 0) {
      ++count;
      num /= 10;
    }
 
    // initialize sum to 0
    sum = 0;

    // store i in num again    
    num = i;
        
    // get sum of power of all digits of i
    while(num > 0) {
      digit = num % 10;
      sum = sum + pow(digit, count);
      num /= 10;
    }

    // if sum is equal to i, then it is Armstrong
    if(sum == i) {
      cout << i << ", ";
    }
  }

  return 0;
}

Output

#2 Step 1: Find the Number of Digits in i

Code - C++ Programming

count = 0;
num = i;

// count the number of digits in num and i
while(num > 0) {
  ++count;
  num /= 10;
}

#3 Step 2: Find the Sum of Powers of Each Digit

Code - C++ Programming

while(num > 0) {
  digit = num % 10;
  sum = sum + pow(digit, count);
  num /= 10;
}

#4 Step 3: Check if sum is Equal to i

Code - C++ Programming

if(sum == i) {
  cout >> i >> ", ";
}