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 | package algs12;
import  stdlib.*;
/* ***********************************************************************
 *  Compilation:  javac Interval2D.java
 *  Execution:    java Interval2D
 *
 *  2-dimensional interval data type.
 *
 *************************************************************************/
public class Interval2D {
  private final Interval1D x;
  private final Interval1D y;
  public Interval2D(Interval1D x, Interval1D y) {
    this.x = x;
    this.y = y;
  }
  // does this interval intersect that one?
  public boolean intersects(Interval2D that) {
    if (!this.x.intersects(that.x)) return false;
    if (!this.y.intersects(that.y)) return false;
    return true;
  }
  // does this interval contain x?
  public boolean contains(Point2D p) {
    return x.contains(p.x())  && y.contains(p.y());
  }
  // area of this interval
  public double area() {
    return x.length() * y.length();
  }
  public String toString() {
    return x + " x " + y;
  }
  public void draw() {
    double xc = (x.left() + x.right()) / 2.0;
    double yc = (y.left() + y.right()) / 2.0;
    StdDraw.rectangle(xc, yc, x.length() / 2.0, y.length() / 2.0);
  }
  // test client
  public static void main(String[] args) {
    args = new String[] { ".3", ".4", ".5", ".6", "1000" };
    double xlo = Double.parseDouble(args[0]);
    double xhi = Double.parseDouble(args[1]);
    double ylo = Double.parseDouble(args[2]);
    double yhi = Double.parseDouble(args[3]);
    int T = Integer.parseInt(args[4]);
    Interval1D xinterval = new Interval1D(xlo, xhi);
    Interval1D yinterval = new Interval1D(ylo, yhi);
    Interval2D box = new Interval2D(xinterval, yinterval);
    box.draw();
    Counter counter = new Counter("hits");
    for (int t = 0; t < T; t++) {
      double x = StdRandom.random();
      double y = StdRandom.random();
      Point2D p = new Point2D(x, y);
      if (box.contains(p)) counter.increment();
      else                 p.draw();
    }
    StdOut.println(counter);
    StdOut.format("box area = %.2f\n", box.area());
  }
}
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