JSFiddle - React, Tailwind, and code Playground

by tara5

JavaScript

var fibonacciArray = [],
    currentNumber = 1,
    prevNumber = 0,
    nextNumber,
    sum = 0,
    lessThan4Million = true;

while (lessThan4Million) {

    nextNumber = currentNumber + prevNumber;
    prevNumber = currentNumber;
    currentNumber = nextNumber;

    if (nextNumber < 4000000) {
        fibonacciArray.push(nextNumber);
        !(nextNumber % 2) && (sum += nextNumber);
    } else {
        lessThan4Million = false;
    }
}

console.log(fibonacciArray);
console.log(sum);