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Arrays
Nested Arrays

Earlier we mentioned that arrays can store other arrays. When an array contains another array it is known as a nested array. Examine the example below:

const nestedArr = [[1], [2, 3]];

To access the nested arrays we can use bracket notation with the index value, just like we did to access any other element:

const nestedArr = [[1], [2, 3]]; console.log(nestedArr[1]); // Output: [2, 3]

Notice that nestedArr[1] will grab the element in index 1 which is the array [2, 3]. Then, if we wanted to access the elements within the nested array we can chain, or add on, more bracket notation with index values.

const nestedArr = [[1], [2, 3]]; console.log(nestedArr[1]); // Output: [2, 3] console.log(nestedArr[1][0]); // Output: 2

In the second console.log() statement, we have two bracket notations chained to nestedArr. We know that nestedArr[1] is the array [2, 3]. Then to grab the first element from that array, we use nestedArr[1][0] and we get the value of 2.

Instructions

1.

Let’s make a nested array! Create a variable numberClusters. Assign as its value an array with three array elements.

  • The first array element should hold the elements 1 and 2 in that order.
  • The second array element should hold the elements 3 and 4 in that order.
  • The third array element should hold the elements 5 and 6 in that order.
2.

Awesome, you made a nested array! Now declare a variable named target using the const keyword and assign to access the element 6 inside numberClusters.

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