Exercise : Rectangle union

• Write an instance method union that will be placed inside the Rectangle class. The method accepts another rectangle r as a parameter and turns the current rectangle into the union of itself and r; that is, modifies the fields so that they represent the smallest rectangular region that completely contains both this rectangle and r.
• For example, the following calls would produce the following rectangles:

  Rectangle rect1 = new Rectangle(5, 12, 4, 6);
  Rectangle rect2 = new Rectangle(6,  8, 5, 7);
  Rectangle rect3 = new Rectangle(14, 9, 3, 3);
  Rectangle rect4 = new Rectangle(10, 3, 5, 8);
  
  rect1.union(rect2);   // {(5, 8), 6x10}
  rect4.union(rect3);   // {(10, 3), 7x9}
  

• Test your solution to this problem in Practice-It.