The ultimate guide to coding interviews: Learn and practice JavaScript design patterns tested by FAANG engineers. Get interview-ready in just a few hours with battle-tested solutions.

If you're an experienced developer, chances are your interviewer won't ask you about language syntax. Instead, they'll focus on things that test your understanding of software architecture, and how capable you are at finding optimized solutions to given problems. 

That’s where a strong understanding of design patterns comes in handy. It's often useful to be able to draw on established patterns instead of reinventing the wheel.

In this course, you will learn how to effectively deploy design patterns to answer interview questions. The course is divided into four sections: Creational Patterns, Structural Patterns, Behavioral Patterns, and Architectural Patterns. Each section has its own set of design patterns which you’ll learn to use through various challenges. 

Every challenge contains a detailed solution explanation. By the end of this course (and with some practice), you will be able to confidently use design patterns to tackle advanced coding interview questions in JavaScript.

JavaScript Design Patterns for Coding Interviews

# Problem statement

In this challenge, you have to use the chain of responsibility pattern to implement the functionality of assigning work to employees.

Each employee has a *name* and a *level* property. The *level* of an employee tells which task they can handle, that is, easy, medium, or hard. Hence, each employee is assigned a task depending on their *level*.

You have already been provided an abstract class `EmployeeChain`. It contains two functions:

* `setNextEmp`: sets the next object in the chain

* `assignWork`: assigns work to an employee depending on their level


You have to use the chain of responsibility pattern to implement these functions, so you can achieve the final goal of assigning work to employees.

# Input

Function `assignWork` is called to assign work to an employee


# Output

A message is displayed that the work has been assigned to the appropriate employee

# Sample input
```
var w1 = new EasyLevelWorkHandler(); 
var w2 = new MediumLevelWorkHandler(); 
var w3 = new HardLevelWorkHandler(); 
w1.setNextEmp(w2); 
w2.setNextEmp(w3); 

const emp1 = new Employee("Joe","Easy")
const emp2 = new Employee("Anne","Medium")
const emp3 = new Employee("Shawn","Hard")
  
w1.assignWork(emp1); 
w1.assignWork(emp2); 
w1.assignWork(emp3); 
```
# Sample output

```
"Easy work assigned to: Joe"	
"Medium work assigned to: Anne"	
"Hard work assigned to: Shawn"
```

In this challenge, you have to implement the chain of responsibility pattern to solve the given problem.

Before We Begin

Introduction To Design Patterns

Creational Patterns

Structural Patterns

Behavioral Patterns

Architectural Patterns

Conclusion

Challenge: Chain of Responsibility Pattern

Problem statement