vladmakohon / ts_figures_classes

Figures

We have 3 types of figures: triangles, circles and rectangles.

Write an interface Figure and 3 classes implementing it so that every figure has:

• a shape (triangle, circle or rectangle);
• a color (red, green or blue);
• a method getArea that returns the area of the figure rounded down to hundredths.

In addition to a color constructors should accept required data:

• sides a, b and c for a triangle;
• a radius for a circle;
• a width and a height for a rectangle.

The constructors should throw new Error('your error message') if:

• any length is <= 0
• the longest side of a triangle is >= than a sum of two others

Hints:

• use Math.PI for calculating a circle square
• use Heron's formula for triangles

Example:

new Rectangle('blue', 2, 0) // throws an error
new Triangle('red', 1, 2, 3) // throws an error: sides 1, 2 and 3 can't form a triangle

Also create a function getInfo that takes a figure and returns a string in the next format:

const redRectangle = new Rectangle('red', 3, 5);
getInfo(redRectangle) === 'A red rectangle - 15';

const greenCircle = new Circle('green', 1);
getInfo(greenCircle) === 'A green circle - 3.14';