using System;
class Rect {
public int width;
public int height;
public Rect(int w, int h) {
width = w;
height = h;
}
public int area() {
return width * height;
}
}
class UseRect {
public static void Main() {
Rect r1 = new Rect(4, 5);
Rect r2 = new Rect(7, 9);
Console.WriteLine("Area of r1: " + r1.area());
Console.WriteLine("Area of r2: " + r2.area());
}
}
Area of r1: 20
Area of r2: 63