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 implement a Ninja fighting game using the prototype pattern. 

You have already been given the `Ninja` constructor function, which will be used to create a *ninja* object. A ninja should have the following properties:

* `name`

* `points`

The `points` are set to `100` by default upon the instantiation of a `Ninja` object.

A ninja can pull the following moves in a fight:

* `punch`: ninjas `points` reduce by `20` if they get a punch

* `kick`: ninjas `points` reduce by `50` if they get a kick

A ninja can only `kick` or `punch` the other ninja if the following conditions are met:

* The other ninja's `points` are greater than `0`.

* The `points` of the ninja himself are also greater than `0`.

If the two conditions above are met, you should return the `points` of the other ninja as follows:

```
`{other ninja's "name"} points are {other ninja's "points"}`
``` 

If the conditions are not met, you should return the following if a punch was attempted:

```
`Can't punch {other ninja's name}`
```
And the following if a kick was attempted:

```
`Can't kick {other ninja's name}`
```



## Input
Two ninjas fighting

## Output
The points of the ninja after being hit or the *"Can't kick/punch"* message

## Sample input

```
var ninja1 = new Ninja('Ninja1')
var ninja2 = new Ninja('Ninja2')

ninja1.kick(ninja2)
ninja2.punch(ninja1)
ninja1.kick(ninja2) 
ninja1.punch(ninja2) 
ninja2.kick(ninja1)
```

## Sample output

```
"Ninja2's points are 50"	
"Ninja1's points are 80"	
"Ninja2's points are 0"
"Can't punch Ninja2"
"Can't kick Ninja1"
```

# Problem statement

In this challenge, you have to implement a Ninja fighting game using the prototype pattern. 

You have already been given the `Ninja` constructor function, which will be used to create a *ninja* object. A ninja should have the following properties:

* `name`

* `points`

The `points` are set to `100` by default upon the instantiation of a `Ninja` object.

A ninja can pull the following moves in a fight:

* `punch`: ninjas `points` reduce by `20` if they get a punch

* `kick`: ninjas `points` reduce by `50` if they get a kick

A ninja can only `kick` or `punch` the other ninja if the following conditions are met:

* The other ninja's `points` are greater than `0`.

* The `points` of the ninja himself are also greater than `0`.

If the two conditions above are met, you should return the `points` of the other ninja as follows:

```
`{other ninja's "name"} points are {other ninja's "points"}`
``` 

If the conditions are not met, you should return the following if a punch was attempted:

```
`Can't punch {other ninja's name}`
```
And the following if a kick was attempted:

```
`Can't kick {other ninja's name}`
```



# Input
Two ninjas fighting

# Output
The points of the ninja after being hit or the *"Can't kick/punch"* message

# Sample input

```
var ninja1 = new Ninja('Ninja1')
var ninja2 = new Ninja('Ninja2')

ninja1.kick(ninja2)
ninja2.punch(ninja1)
ninja1.kick(ninja2) 
ninja1.punch(ninja2) 
ninja2.kick(ninja1)
```

# Sample output

```
"Ninja2's points are 50"	
"Ninja1's points are 80"	
"Ninja2's points are 0"
"Can't punch Ninja2"
"Can't kick Ninja1"
```

In this challenge, you have to implement the prototype pattern to solve the given problem.

Before We Begin

Introduction To Design Patterns

Creational Patterns

Structural Patterns

Behavioral Patterns

Architectural Patterns

Conclusion

Challenge: Prototype Pattern

Problem statement