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Modify Array Data With Indexes

curriculum/challenges/english/blocks/basic-javascript/cf1111c1c11feddfaeb8bdef.md

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--description--

Unlike strings, the entries of arrays are <dfn>mutable</dfn> and can be changed freely, even if the array was declared with const.

Example

js
const ourArray = [50, 40, 30];
ourArray[0] = 15;

ourArray now has the value [15, 40, 30].

Note: There shouldn't be any spaces between the array name and the square brackets, like array [0]. Although JavaScript is able to process this correctly, this may confuse other programmers reading your code.

--instructions--

Modify the data stored at index 0 of myArray to a value of 45.

--hints--

myArray should now be [45, 64, 99].

js
assert(
  (function () {
    if (
      typeof myArray != 'undefined' &&
      myArray[0] == 45 &&
      myArray[1] == 64 &&
      myArray[2] == 99
    ) {
      return true;
    } else {
      return false;
    }
  })()
);

You should be using correct index to modify the value in myArray.

js
assert(
  (function () {
    if (__helpers.removeJSComments(code).match(/myArray\[0\]\s*=\s*/g)) {
      return true;
    } else {
      return false;
    }
  })()
);

--seed--

--seed-contents--

js
// Setup
const myArray = [18, 64, 99];

// Only change code below this line

--solutions--

js
const myArray = [18, 64, 99];
myArray[0] = 45;