#include <iostream>

using namespace std;
int main(){
    int choice=0; 
    
    bool isUsed1=false, isUsed2=false;
    
    while (true){
        cout << "Choose a number 1 or 2: ";
        cin >> choice;
        
        if (choice == 1){
            isUsed1 = true;
        }
        else {
            isUsed2 = true;
        }
        
        if (isUsed1 == true && isUsed2==true){
            break;
        }
    }
 
    
 return 0;
}