How to add string to the end of each array element using a for loop?

Question

I am to finish the function below. I am to loop through the arr paramteter using a for loop and add the string "Duck" to the end of each element (i.e. arr[0] = "yellow"; should become "yellowDuck".

Here is what I am given to start with:

function addDucks(arr, ind) {
 //WRITE YOUR FOR-LOOP HERE
 //For your iterator, declare it with the let keyword, and name it "i"
 //DO NOT TOUCH THIS
 return [arr, ind]
} 

Here is the code I am trying:

function addDucks(arr, ind) {
 for (let i = 0; i < arr.length; i++) {
 return arr[i] + 'Duck';
 }
 return [arr, ind]
}

• bmartin: What is the issue that you are encountering when running the code you wrote. What do you expect to happen?
• stoney_24: @bmartin I expect it to pass these tests: should return an array the first element of the returned array should be the passed-in array with "Duck" added to every element the second element of the returned array should be 3 when passed [1, 2, 3], 3
• bmartin: As the answer below states - you are returning the concatenation of only the first element, instead of modifying the array's values.
• HMR: Tell your teacher the right answer is: "You don't use a for loop, that's what map was created for" but if you insist on mutating there is also forEach
• stoney_24: @HMR I know. I think it's just to make sure we know about for loops as well.

Answer 1

Your code was close, you were just not changing the reference in the array to be the string with Duck added. Modified the return arr[i] + 'Duck' to arr[i] += 'Duck' which is the same as arr[i] = arr[i] + 'Duck'

function addDucks(arr, ind) {
 for (let i = 0; i < arr.length; i++) {
 arr[i] += 'Duck';
 }
 return arr;
}
let ducks = addDucks(['green','purple'], 2);
console.log(ducks);