# Stuck on Iterate Through an Array with a For Loop

So I got the hang of the other loop lessons, but I’m stuck on this one.

My error messages are

total should equal 20

I’m not sure how to get total to equal 20. Making i = 20 doesn’t work so I’m stumped.

You should use a for loop to iterate through myArr

I thought that was what I doing here, so I’m not sure why my for loop isn’t a for loop.

``````// Setup
const myArr = [2, 3, 4, 5, 6];
for (let i = 0; i < myArr.length; i++){
let total = 0;
total += myArr;
}
// Only change code below this line

``````
``````  **Your browser information:**
``````

User Agent is: `Mozilla/5.0 (iPad; CPU iPhone OS 15_5 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) FxiOS/102.0 Mobile/15E148 Safari/605.1.15`

Challenge: Iterate Through an Array with a For Loop

Can someone explain why adding total +=myArr[i]; make the for loop work properly now? Is this something to do with bracket notation?

``````// Setup
const myArr = [2, 3, 4, 5, 6];
for (let i = 0; i < myArr.length; i++){
let total = 0;
total += myArr[i];
}
// Only change code below this line

``````

If you’ve forgotten about accessing values inside arrays check out this lesson:

`myArray` is an array with 5 values inside.

``````console.log(myArray);    // [2, 3, 4, 5, 6]
console.log(myArray); // 2
console.log(myArray); // 3
console.log(myArray); // 4
console.log(myArray); // 5
console.log(myArray); // 6
``````

The numbers we use to access a certain value are called an “index”. Notice the “0” index refers to the first value in the array, the “1” index refers to the second value, and so on.

Back to the lesson you’re asking about, it explains that a common task is to “loop through” an array, accessing each of its values in turn. In this lesson we want to use that technique to calculate the `total` of all the numbers in `myArray`.

Here’s the starter code:

``````// Setup
const myArr = [2, 3, 4, 5, 6];

// Only change code below this line
``````

And here’s the 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`.

So, here are the steps:

1. declare a variable named `total` and assign it the value `0`
2. using a for loop, access each value in `myArray` in turn, and add it to `total`

Notice, declaring `total` needs to happen before the for loop.

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You cannot declare total inside the for loop, put it before.

1 Like

…I just realised the numbers in myArr when added equal 20.

The whole thing makes sense now, I was confused where the 20 came from and forgot to try doing basic maths. It makes sense to add the numbers in the array to total to get total to equal 20.

Okay solved it! Thanks!