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

console.log('What\'s your age ? ')
process.stdin.on('data', function(age) {
        if (isNaN(age)) {
                console.log ('Not a Number!')
        }else{
                if( (age > 0) && (age < 99) ){
                console.log('Your year of birth is ' + (2019 - age) )
                } else {
                console.log('Try again')
                }}
          process.exit()
})