Object Oriented Programming with Dart

Object Oriented Programming with Dart.dart

//Created by Dipansh Khandelwal
// Github @DipanshKhandelwal

import 'dart:math';

abstract class Shape {
    List<double> sides;
    double perimeter;
  
    Shape(this.sides) {
        this.perimeter = this.sides.reduce((a, b) => a + b);
    }

    double area(); 
}

class Triangle extends Shape {
    Triangle(double a, double b, double c) : super([a,b,c]);

    double area() {
        double s = this.perimeter/2;
        return sqrt(s * (s - sides[0]) * (s - sides[1]) * (s - sides[2]));
    }
}

class Rectangle extends Shape {
    Rectangle(double a, double b) : super([a,b]);

    double area() {
        return sides[0]*sides[1];
    }
}

void main() {
    Triangle triangle = new Triangle(3.0, 4.0, 5.0);
    Rectangle rectangle = new Rectangle(4.0, 5.0);
    print('Area of triangle is ${triangle.area()}, its perimeter is ${triangle.perimeter}');
    print('Area of rectangle is ${rectangle.area()}, its perimeter is ${rectangle.perimeter}');
}