Array data structure

This tutorial is a part of the Data Structures and Algorithms class:

• How data looks like (print it out!)
• How to insert/delete/access/search data
• How fast to insert/delete/access/search data

Array data structure:

• is one of the most popular data structures.
• is usually used to store a large amount of data with similar pattern.
• built-in in Javascript.
• ordered elements.

How data looks like (print it out!)

// initialize
const arr = ['a', 'b', 4, 2, 'v']

// print out, see how data looks like
console.log(arr) // [ 'a', 'b', 4, 2, 'v' ]

$ node array-data-structure.js
[ 'a', 'b', 4, 2, 'v' ]

How to insert/delete/access/search data

// insert
arr.push(100)
console.log(arr) // [ 'a', 'b', 4, 2, 'v', 100 ]

arr.splice(1, 0, 'Data Structure');
console.log(arr) // [ 'a', 'Data Structure', 'b', 4, 2, 'v', 100 ]

// delete
arr.splice(4,1)
console.log(arr) // [ 'a', 'Data Structure', 'b', 4, 'v', 100 ]

// access
console.log(arr[1]) // Data Structure

// search
console.log(arr.includes(100)) // true
console.log(arr.includes(200)) // false

$ node array-data-structure.js
[ 'a', 'b', 4, 2, 'v', 100 ]
[ 'a', 'Data Structure', 'b', 4, 2, 'v', 100 ]
[ 'a', 'Data Structure', 'b', 4, 'v', 100 ]
Data Structure
true
false

Make sure to checkout Array's popular methods in Javascript to know all possible operations.

How fast to insert/delete/access/search data

⬆️ Time complexity (worst case) per operation

Real life interview questions

1. Do you know how your data looks like?
2. What kind of information can array data structure store in real life applications?
3. How do you insert/delete/access/search with array data structure?
4. What is the Time Complexity of array data structure on insert/delete/access/search operation?
5. Find4: Given an array of random integer, example: [2, 4, 5, 1, 6], and a random sum, example: 13. Write a function to return 4 numbers that their combination equals to the sum, example: [2, 4, 1, 6].