HTMLify

/**
 * @param {number} n
 * @return {number}
 */
var fib = function(n) {
    if (n == 0)
        return 0;
    if (n == 1)
        return 1;
    const fibo = [0, 1];
    for (let i = 0; i < n-1; i++)
        fibo.push(fibo[fibo.length-1] + fibo[fibo.length-2]);
    return fibo[fibo.length-1];
};