Data Structures Introduction

#javascript #html #css #webdev

                   -Which Data Structure is The Best?
                   -ES2015 Class Syntax Overview
                   -Data Structure: The Class Keyword
                   -Data Structure: Adding Instance Methods

Which Data Structure is The Best?

Data structures are collections of values, the relationships among them, and the functions or operations that can be applied to the data. Data structures excel at different things. Some are highly specialized, while others are more generally used.

Visualized Data Structures

Array

Singly Linked List

Hash Table

Tree

Binary Search Tree

Undirected Graph

Directed Graph

All data structures store data, however the relationship between the data and the functionality between methods differ.

ES2015 Class Syntax Overview

What is a class?
A class is a blueprint for creating objects with pre-defined properties and methods.

Class example


class Student {
    constructor(firstName, lastName, year){
        this.firstName = firstName;
        this.lastName = lastName;
        this.grade = year;
    }
}

let firstStudent = new Student("Colt", "Steele",1);
let secondStudent = new Student("Blue", "Steele",2);

The method to create new objects must be called constructor.
The class keyword creates a constant that can not be redefined.

Data Structure: Adding Instance Methods


class Student {
    constructor(firstName, lastName, year){
        this.firstName = firstName;
        this.lastName = lastName;
        this.grade = year;
        this.tardies = 0;
        this.scores = [];
    }
    fullName(){
        return `Your full name is ${this.firstName} ${this.lastName}`;
    }
    markLate(){
        this.tardies += 1;
        if(this.tardies >= 3) {
            return "YOU ARE EXPELLED!!!!"
        }
        return `${this.firstName} ${this.lastName} has been late ${this.tardies} times`;
    }
    addScore(score){
        this.scores.push(score);
        return this.scores
    }
    calculateAverage(){
        let sum = this.scores.reduce(function(a,b){return a+b;})
        return sum/this.scores.length;
    }  
}

let firstStudent = new Student("Colt", "Steele",1);
let secondStudent = new Student("Blue", "Steele",2);