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JavaScript JavaScript Array Iteration Methods Combining Array Methods Array Flattening

Posted by Hanwen Zhang
Hanwen Zhang
20,084 Points

Please help, my code is not working, unexpected token...

Using reduce method, flatten the customerNames array of arrays. In other words, take all the names from each array inside customerNames and place them in one big array. Store the flattened array in the flattenedCustomerNames variable. You can use the array in the comments below for reference.

app.js 
const customerNames = [
    [ "John", "Sandy", "Tyrone", "Elizabeth", "Penny" ],
    [ "Barry", "Wanda", "Jamal", "Hayden" ],
    [ "Portia", "Pam", "Philip" ]
];
let flattenedCustomerNames;

// flattenedCustomerNames should be: ["John", "Sandy", "Tyrone", "Elizabeth", "Penny", "Barry", "Wanda", "Jamal", "Hayden", "Portia", "Pam", "Philip"]
// Write your code below

flattenedCustomerNames = customerNames.reduce((total, name) => [...total, ...name), []);

1 Answer

Peter Vann
Peter Vann
36,425 Points

Hi Hanwen!

You are so close!

Your issue is you have one ) where you should have a ]

See if you can spot it and correct it.

Obviously, it's merely a typo/oversight.

Clearly, you were attempting the correct way to code it to pass.

I hope that helps.

Stay safe and happy coding!

Hanwen Zhang
Hanwen Zhang
20,084 Points

Passed!! thank you for spotting the typo