Int to Roman

let intToRoman = function(num) {

    const mapping = {
        1000: 'M',
        900:  'CM',
        500:  'D',
        400:  'CD',
        100:  'C',
        90:   'XC',
        50:   'L',
        40:   'XL',
        10:   'X',
        9:    'IX',
        5:    'V',
        4:    'IV',
        1:    'I'
    }

    let result = "";
    for(let divisor of [1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1]) {
        if (num >= divisor) {
            let quotient = Math.floor(num / divisor);
            result = result + mapping[divisor].repeat(quotient);
            num = num % divisor;
        }
    }

    return result;
}