rectangle – Rectangle – Computer Science by Example

rectangle – Rectangle

A rectangle

Write a program that reads a pair of numbers representing the width and height of a rectangle and prints its area an perimeter. Here is an example of how a console session with this program should look like:

$ ./rectangle
1 2
1x2 rectangle, area = 2, perimeter = 6
3 6
3x6 rectangle, area = 18, perimeter = 18
10 1
10x1 rectangle, area = 10, perimeter = 22

Tip: use control+D (^D) to simulate the end of file and exit the program.

Input and Output

Each line of input contains two numbers w and h where -1 000 ≤ w, h ≤ 1 000

For each line of input there should be one line of output in the following format:

<W>x<H> rectangle, area = <AREA>, perimeter = <PERIMETER>

Replace <W>, <H>, <AREA> and <PERIMETER> by the width, height, area and perimeter of the given rectangle respectively.

Example input

1 2
3 6
10 1

Example output

1x2 rectangle, area = 2, perimeter = 6
3x6 rectangle, area = 18, perimeter = 18
10x1 rectangle, area = 10, perimeter = 22

The `area` and `perimeter` functions

In order to get a full score, your program should be implemented using functions area and perimeter. They should receive a rectangle object. Please refer to the information for your chosen language.

C

struct rectangle {
    int width;
    int height;
};
int area(struct rectangle rectangle);
int perimeter(struct rectangle rectangle);

Python

class Rectangle:
    def __init__(self, width, height):
        self.width = width
        self.height = height

    def area(self):
        ...

    def perimeter(self):
        ...

Haskell

data Rectangle = Rectangle { width :: Int
                           , height :: Int
                           }
area :: Rectangle -> Int
perimeter :: Rectangle -> Int

Alternatively, you can declare the rectangle type as:

data Rectangle = Rectangle Int Int

C++

class rectangle
{
    public:
    int width;
    int height;
    int area();
    int perimeter();
};

C♯

class Rectangle
{
    public int Width { get; set; }
    public int Height { get; set; }
    public Rectangle(int width, int height);
    public int Area();
    public int Perimeter();
}

Java

public class Rectangle
{
    public int width;
    public int height;
    public Rectangle(int width, int height);
    public int area();
    public int perimeter();
}

JavaScript

rectangle = {width: ..., height: ...}
function area(rectangle)
function perimeter(rectangle)

Lua

rectangle = {width = ..., height = ...}
function area(rectangle)
function perimeter(rectangle)

Ruby

class Rectangle
  attr_reader :width
  attr_reader :height

  def initialize(width, height)
    @width = width
    @height = height
  end

  def area
    ...
  end

  def perimeter
    ...
  end
end

Racket

(define (area rectangle) ...)
(define (perimeter rectangle) ...)
; where a rectangle is represented by (cons w h)

Scheme

(define (area rectangle) ...)
(define (perimeter rectangle) ...)
;;; where a rectangle is represented by (cons w h)

R

rectangle = list(width = ..., height = ...)
area <- function (rectangle)
perimeter <- function (rectangle)

Scoring

1/3: works for the above example
2/3: works for other test cases
3/3: implements the area and perimeter functions over the required rectangle type

try first: replace mult box

index | submit | rank | book