Array Challenges

Now that we have gone over some basic array stuff, let's try some simple challenges. I would suggest trying these using just what you remember from the past sections, but if you need to look back, that's fine as well.

Note: When I assign a challenge, I will never ask you to do something that we have not went over yet in the course. For example, I would not ask you to create a function because we haven't talked about functions yet. Because of this, some of the earlier challenges may seem a bit easy to some of you that already have experience with JavaScript.

Challenge 1:

Instructions:

Use some of the array methods that we looked at to mutate the following array to = the expected result below:

const arr = [1, 2, 3, 4, 5];

Expected Result:

console.log(arr);
// [6, 5, 4, 3, 2, 1, 0];

Hint: No hints. This one is pretty easy ;)

Click For Solution

const arr = [1, 2, 3, 4, 5];

  arr.unshift(0);
  arr.push(6);
  arr.reverse();

  console.log(arr); // [6, 5, 4, 3, 2, 1, 0];

Challenge 2:

Instructions:

Combine arr1 and arr2 into a new array called arr3 with the following elements:

const arr1 = [1, 2, 3, 4, 5];
const arr2 = [5, 6, 7, 8, 9, 10];

Notice that both arr1 and arr2 include the number 5. You will have to find a way to get rid of the extra 5.

Expected Result:

console.log(arr3);
// [1,2,3,4,5,6,7,8,9,10]

Hint: There are many ways to do this, but think of the concat() method or the spread operator as well as the slice() or splice() methods

Click For Solution

const arr1 = [1, 2, 3, 4, 5];
const arr2 = [5, 6, 7, 8, 9, 10];

// Solution 1
const arr3 = arr1.slice(0, 4).concat(arr2);

console.log(arr3); // [1,2,3,4,5,6,7,8,9,10]

// Solution 2
const arr4 = [...arr1, ...arr2];
arr4.splice(4, 1);

console.log(arr4); // [1,2,3,4,5,6,7,8,9,10]