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package algs34;
import stdlib.*;
import java.util.HashSet;
/* ***********************************************************************
 *  Compilation:  javac PhoneNumber.java
 *  Execution:    java PhoneNumber
 *  Dependencies:
 *
 *  Immutable data type for US phone numbers.
 *
 *************************************************************************/

public final class XPhoneNumber {
  private final int area;   // area code (3 digits)
  private final int exch;   // exchange  (3 digits)
  private final int ext;    // extension (4 digits)

  public XPhoneNumber(int area, int exch, int ext) {
    this.area = area;
    this.exch = exch;
    this.ext  = ext;
  }

  // how you're supposed to implement equals
  public boolean equals(Object y) {
    if (y == this) return true;
    if (y == null) return false;
    if (y.getClass() != this.getClass()) return false;
    XPhoneNumber that = (XPhoneNumber) y;
    if (!((this.area == that.area) && (this.exch == that.exch) && (this.ext == that.ext))) return false;
    return true;
  }

  // satisfies the hashCode contract
  public int hashCode() {
    int h = 17;
    h = ext + 31 * h;
    h = exch + 31 * h;
    h = area + 31 * h;
    return h;
  }

  // 0 for padding with leading 0s
  public String toString() {
    return String.format("(%03d) %03d-%04d", area, exch, ext);
  }

  public static void main(String[] args) {
    XPhoneNumber a = new XPhoneNumber(609, 258, 4455);
    XPhoneNumber b = new XPhoneNumber(609, 876, 5309);
    XPhoneNumber c = new XPhoneNumber(609, 003, 5309);
    XPhoneNumber d = new XPhoneNumber(215, 876, 5309);
    XPhoneNumber e = new XPhoneNumber(609, 876, 5309);
    StdOut.format("a = %s [hashcode=%d]\n", a, a.hashCode ());
    StdOut.format("b = %s [hashcode=%d]\n", b, b.hashCode ());
    StdOut.format("c = %s [hashcode=%d]\n", c, c.hashCode ());
    StdOut.format("d = %s [hashcode=%d]\n", d, d.hashCode ());
    StdOut.format("e = %s [hashcode=%d]\n", e, e.hashCode ());

    HashSet<XPhoneNumber> set = new HashSet<>();
    set.add(a);
    set.add(b);
    set.add(c);
    StdOut.println("Added a, b, and c");
    StdOut.println("contains a:  " + set.contains(a));
    StdOut.println("contains b:  " + set.contains(b));
    StdOut.println("contains c:  " + set.contains(c));
    StdOut.println("contains d:  " + set.contains(d));
    StdOut.println("contains e:  " + set.contains(e));
    StdOut.println("b == e:      " + (b == e));
    StdOut.println("b.equals(e): " + (b.equals(e)));
  }



}