Write a program in C++ to check Armstrong number of n digits. .

.#include <iostream>
using namespace std;
void main()
{

 int n1, onum, r, result = 0, n = 0 ;
    cout<<" Check whether an n digits number is armstrong or not :\n";
    cout<<" Input  an integer : ";
    cin>>n1;
     onum = n1;
    while (onum != 0)
    {
        onum /= 10;
        ++n;
    }

    onum = n1;

    while (onum != 0)
    {
        r = onum % 10;
        result += pow(r, n);
        onum /= 10;
    }

    if(result == n1)
        cout<<n1<<" is an Armstrong number.\n";
    else
        cout<<n1<<" is not an Armstrong number.\n";
      cout<<endl;
         system ("pause");
}


Test Data :
Input an integer : 1634
Expected Output :
1634 is an Armstrong number