Prime or Composite do while

#include <iostream>
using namespace std;
int main(){
    int num2, two_numbers, input;
    cout << "Enter a Number: ";
    cin >> input;
    num2=1;
    do{
        //Reset to 0
        two_numbers=0;
        if(input==0){
            cout << input << " is neither a prime number nor a composite number . . .";
        }
        else if(input!=0){
            do{
                if (input%num2==0){
                    two_numbers++;
                }
                num2++;
            }while(num2<=input);
        }
    }while (num2<=input);
    if (two_numbers==2){
        cout << input << " is a prime number . . .";
    }
    else if (two_numbers!=2){
        cout << input << " is a composite number . . .";
    }
}