Question

In C++, create an input validation where the user enters a signed whole number and repeats this process until the user enters a zero. Do not accept any value with a decimal fraction or other extraneous characters, including dollar signs. The number's sign must be preserved. Some of the steps has been done for you. Fill out the program in C++. See below for the expected console output.

Program:

#include <iostream>

using namespace std;

int main(){
  
signed int input;
  
cout << "Enter a whole number: ";
  
cin>> input;
  
}

Expected Console Outputs:

Enter a number: $3444

Invalid input; try again.

Enter a number: $333

Invalid input; try again.

Enter a number: 344

Good input!

Enter a number: 344a

Invalid input; try again.

Enter a number: -344

Good input!

Enter a number: ddd

Invalid input; try again.

Enter a number: aaa

Invalid input; try again.

Answer 1

#include <iostream>

using namespace std;

int main() {
    signed int input;
    while (1) {
        cout << "Enter a number: ";
        if (cin >> input) {
            if (input == 0)
                break;
            cout << "Good input!" << endl;
        } else {
            cout << "Invalid input; try again." << endl;
            cin.clear();
            cin.ignore(numeric_limits<streamsize>::max(), '\n');
        }
    }
    return 0;
}