#include <iostream>

using namespace std;

/* WHILE loop

while(condition)
    command to be executed while the condition is satisfied

*/

int main()
{
    int age;
    cout << "Please enter your age: ";
    cin >> age;

    while(cin.fail())      // it returns true if the input buffer has been given wrong data
    {
        cout << "You've entered the wrong data. Please enter your age again: ";
        cin.clear();                    // hides the error flag
        cin.ignore(99999, '\n');        // empties the buffer
        cin >> age;
    }

    cout << "You are " << age << " years old. ";
    if(age > 17)
        cout << "You are an adult.\n";
    else
        cout << "You are not an adult.\n";

    return 0;
}