function fizzBuzz(num) {
    if (typeof num !== 'number' || num == undefined ) {
        return false
    }
    let a = num % 3 == 0 ? 2: 1;
    let b = num % 5 == 0 ? 8: 4;
    let obj = {
        5:  num,
        6: 'fizz',
        9: 'buzz',
        10: 'fizzbuzz'
    }
    return obj [a+b ]
}