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]
}

What is the issue that you are encountering when running the code you wrote. What do you expect to happen? — bmartin
– bmartin, Commented Jun 4, 2018 at 22:44
@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 — stoney_24
– stoney_24, Commented Jun 4, 2018 at 22:45
As the answer below states - you are returning the concatenation of only the first element, instead of modifying the array's values. — bmartin
– bmartin, Commented Jun 4, 2018 at 22:48
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 — HMR
– HMR, Commented Jun 4, 2018 at 23:17
@HMR I know. I think it's just to make sure we know about for loops as well. — stoney_24
– stoney_24, Commented Jun 4, 2018 at 23:42

pmkro · Accepted Answer · 2018-06-04 22:52:55Z

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);

answered Jun 4, 2018 at 22:52

pmkro

2,5482 gold badges19 silver badges25 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

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

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related