Armstrong no. sum error

Question

#include<iostream>
#include<cmath>

using namespace std ;
int countNum (int) ;
int isArmstrongNum (int) ;

int countNum(int n){
int digit=0;

while (n>0){
n=n/10 ;
digit++ ;
}
return digit ;

}
int isArmstrong (int n){
int temp,power, sum=0;
temp = n;
power = countNum(n);
while(n>0){
sum = sum + pow (n%10, power) ;
n=n/10 ;
}
return sum==temp;
}

int main(){
int lower, upper, sum=0 ;
cout<< "Enter the lower and upper limit"<<endl;
cin>>lower;
cin>>upper;
while (lower>=upper){
if (isArmstrong(lower)){
sum+=lower ;
lower++ ;

}
}
cout<< sum ;
return 0;
}

The isArmstrong function is working but i'm am not getting the sum for lower and upper limit. Can Someone Please point out the error.

Answer 1

please use the code playground for easy debugging

Answer 2

Can you give an example? I couldn't find any bugs.
Maybe it is better for larger numbers to use long instead of int.

Answer 3

int main (){
int i, sum=0;
cout << "Enter a Number"<<endl ;
for (i=1 ; i <= 50000 ; i++){
if (isArmstrong(i)){
cout << i <<endl;
}
}
return 0 ;
}

if i replace last para of code with this then its show all the armstrong no between 1 to 50000