Data structures: Arrays

What is it?

An ordered list of items.

const names = ['Jim', 'Bob', 'Alice']

Big O

• Access: O(1)
• Insertion
  • Insertion at the end: O(1)
  • Insertion at the beginning: O(n) – We have to re-index all the other elements in the existing array.
• Removal
  • Removal at the end: O(1)
  • Removal at the beginning: O(n) – We have to re-index all the other elements in the existing array.
• Searching: O(n)

When to use?

• When you need the items to be ordered.
• You need fast insertion and access.