What is the output of the following? “`js const arr = [1, 2, 3]; arr[10] = 99; console.log(arr.length); console.log(arr[5]); “`

Question

JavaScript Professional — Medium

What is the output of the following? “`js const arr = [1, 2, 3]; arr[10] = 99; console.log(arr.length); console.log(arr[5]); “`

Accepted Answer

The output will be 11, undefined. When you assign a value to an index that is beyond the current length of the array, JavaScript automatically increases the length of the array to accommodate the new index. However, the values between the last index and the new index will be undefined.