freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../basic-javascript/iterate-through-an-array-wi...

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---
id: 5675e877dbd60be8ad28edc6
title: Iterate Through an Array with a For Loop
challengeType: 1
videoUrl: 'https://scrimba.com/c/caeR3HB'
forumTopicId: 18216
dashedName: iterate-through-an-array-with-a-for-loop
---
# --description--
A common task in JavaScript is to iterate through the contents of an array. One way to do that is with a `for` loop. This code will output each element of the array `arr` to the console:
```js
2019-12-02 23:42:32 +00:00
var arr = [10, 9, 8, 7, 6];
for (var i = 0; i < arr.length; i++) {
console.log(arr[i]);
}
```
Remember that arrays have zero-based indexing, which means the last index of the array is `length - 1`. Our condition for this loop is `i < arr.length`, which stops the loop when `i` is equal to `length`. In this case the last iteration is `i === 4` i.e. when `i` becomes equal to `arr.length` and outputs `6` to the console.
# --instructions--
Declare and initialize a variable `total` to `0`. Use a `for` loop to add the value of each element of the `myArr` array to `total`.
# --hints--
`total` should be declared and initialized to 0.
```js
assert(code.match(/(var|let|const)\s*?total\s*=\s*0.*?;?/));
```
`total` should equal 20.
```js
assert(total === 20);
```
You should use a `for` loop to iterate through `myArr`.
```js
assert(/for\s*\(/g.test(code) && /myArr\s*\[/g.test(code));
```
You should not attempt to directly assign the value 20 to `total`.
```js
assert(!__helpers.removeWhiteSpace(code).match(/total[=+-]0*[1-9]+/gm));
```
# --seed--
## --after-user-code--
```js
(function(){if(typeof total !== 'undefined') { return "total = " + total; } else { return "total is undefined";}})()
```
## --seed-contents--
```js
// Setup
var myArr = [ 2, 3, 4, 5, 6];
// Only change code below this line
```
# --solutions--
```js
var myArr = [ 2, 3, 4, 5, 6];
var total = 0;
for (var i = 0; i < myArr.length; i++) {
total += myArr[i];
}
```