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JavaScript JavaScript Loops Working with 'for' Loops The Refactor Challenge – One Solution

Gal Parselany
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Gal Parselany
Full Stack JavaScript Techdegree Graduate 26,281 Points

My solution is good aswell? I dont use the let before the for loops, but only inside the for loops. is that ok?

let html = '';
for (i = 1; i <= 10; i++) {
    let red = Math.floor(Math.random() * 256);
    let green = Math.floor(Math.random() * 256);
    let blue = Math.floor(Math.random() * 256);
    let randomRGB = `rgb( ${red}, ${green}, ${blue} )`;
    html += `<div style="background-color: ${randomRGB}">${i}</div>`;
}
document.querySelector('main').innerHTML = html;

is that ok too? cause I see that Guil is still using the vars outside the for loops, and I dont understand if its necessary. thanks in advance

1 Answer

Steven Parker
Steven Parker
229,644 Points

By declaring the variables outside the loop, Guil's code inside the loop becomes a simple assignment making the loop more efficient.

Declaring the variables inside the loop will do the same job, but they will be disposed and then re-created for each iteration, using a bit more processor time. But since the loop is simple and short, the difference won't be noticed.