process.stdin.resume();
process.stdin.setEncoding('utf8');

console.log('How old are you?');

process.stdin.on('data', (age) => {
    const birthYear = 2019 - age;

    if (isNaN(age) === false && age >0 && age <= 99) {
        console.log(`You were born in ${birthYear}`);
        process.exit()

        }
        else if (age > 99) {
            console.log(`Sorry, you are too old to use this function.`);
        }
    else {
        console.log(`You should mention your age in numerical values.`);
    }
});