Exercism-JS/vehicle-purchase

Vehicle Purchase

Welcome to Vehicle Purchase on Exercism's JavaScript Track. If you need help running the tests or submitting your code, check out HELP.md. If you get stuck on the exercise, check out HINTS.md, but try and solve it without using those first :)

Introduction

Comparison

In JavaScript, numbers can be compared using the following relational and equality operators.

Comparison	Operator
Greater than	a > b
Greater than or equals	a >= b
Less than	a < b
Less than or equals	a <= b
(Strict) Equals	a === b
Not (strict) equals	a !== b

The comparison result is always a boolean value: true or false.

1 < 3;
// => true

2 !== 2;
// => false

1 === 1.0;
// => true
// All numbers are floating-points, so this is different syntax for
// the exact same value.

In JavaScript, the comparison operators above can also be used to compare strings. In that case, a dictionary (lexicographical) order is applied. You can find a list of the exact order of all the characters here.

'Apple' > 'Pear';
// => false

'a' < 'above';
// => true

'a' === 'A';
// => false

Conditionals

A common way to conditionally execute logic in JavaScript is the if-statement. It consists of the if keyword, a condition wrapped in round brackets and a code block wrapped in curly brackets. The code block will only be executed if the condition evaluates to true.

if (condition) {
  // code that is executed if "condition" is true
}

It can be used stand-alone or combined with the else keyword.

if (condition) {
  // code that is executed if "condition" is true
} else {
  // code that is executed otherwise
}

To nest another condition into the else statement, you can use else if.

if (condition1) {
  // code that is executed if "condition1" is true
} else if (condition2) {
  // code that is executed if "condition2" is true
  // but "condition1" was false
} else {
  // code that is executed otherwise
}

Instructions

In this exercise, you will write some code to help you prepare to buy a vehicle.

You have three tasks, one to determine if you will need to get a licence, one to help you choose between two vehicles and one to estimate the acceptable price for a used vehicle.

1. Determine if you will need a drivers licence

Some kinds of vehicles require a drivers license to operate them. Assume only the kinds 'car' and 'truck' require a license, everything else can be operated without a license.

Implement the needsLicense(kind) function that takes the kind of vehicle and returns a boolean indicating whether you need a license for that kind of vehicle.

needsLicense('car');
// => true

needsLicense('bike');
// => false

2. Choose between two potential vehicles to buy

You evaluate your options of available vehicles. You manage to narrow it down to two options but you need help making the final decision. For that implement the function chooseVehicle(option1, option2) that takes two vehicles as arguments and returns a decision that includes the option that comes first in dictionary order.

chooseVehicle('Wuling Hongguang', 'Toyota Corolla');
// =>  'Toyota Corolla is clearly the better choice.'

chooseVehicle('Volkswagen Beetle', 'Volkswagen Golf');
// =>  'Volkswagen Beetle is clearly the better choice.'

3. Calculate an estimation for the price of a used vehicle

Now that you made your decision you want to make sure you get a fair price at the dealership. Since you are interested in buying a used vehicle, the price depends on how old the vehicle is. For a rough estimate, assume if the vehicle is less than 3 years old, it costs 80% of the original price it had when it was brand new. If it is more than 10 years old, it costs 50%. If the vehicle is at least 3 years old but not older than 10 years, it costs 70% of the original price.

Implement the calculateResellPrice(originalPrice, age) function that applies this logic using if, else if and else (there are other ways but you want to practice). It takes the original price and the age of the vehicle as arguments and returns the estimated price in the dealership.

calculateResellPrice(1000, 1);
// => 800

calculateResellPrice(1000, 5);
// => 700

calculateResellPrice(1000, 15);
// => 500

Source

Created by

• @junedev

Contributed to by

• @SleeplessByte