// Hw5.java
// <Your Name>, <Your Andrew ID>, <Your Section>

public class Hw5 {

  ////////////////////////////////////////////////////
  /// your methods
  ////////////////////////////////////////////////////

  // This method takes a String and an index and returns the integer value
  // of the digit at the given index.  For example, given "84+23" and
  // index 0, the method returns the value 8.  If the index is not in bounds
  // or there is not a digit at that location of the String, the method
  // should return -1.
  public static int digitAt(String s, int index) {
    return 42;
  }

  // This method takes four doubles representing the two lines y=m1*x+b1 and
  // y=m2*x+b2 and returns an int value representing the quadrant where these
  //  two lines intersect, or -1 if they do not intersect in a single point
  // (either because they are parallel or they are in fact the same line).
  // Quadrants are numbered normally, so 1 is the top-right, 2 top-left,
  // 3 bottom-left, and 4 bottom-right.  If the two lines intersect at (or
  // "very nearly" at) the origin, you should return a 0.  If the intersect
  // directly on the x or y axis, but not at the origin, do something
  // reasonable (your choice, just be consistent and document your design).
  public static int quadrantOfIntersection(double m1, double b1,
                                           double m2, double b2) {
    return 42;
  }

  // This method takes an integer n and returns true if it is a Fibonacci
  // number and false otherwise, using the approach described in the
  // hw5 writeup.
  public static boolean isFibonacciNumber(int n) {
    return false;
  }

  ////////////////////////////////////////////////////
  /// test methods for your methods
  ////////////////////////////////////////////////////

  public static void testDigitAt() {
    System.out.print("Testing digitAt... ");
    assert(digitAt("84+23",-1) == -1);
    assert(digitAt("84+23", 0) == 8);
    assert(digitAt("84+23", 1) == 4);
    assert(digitAt("84+23", 2) == -1);
    assert(digitAt("84+23", 3) == 2);
    assert(digitAt("84+23", 4) == 3);
    assert(digitAt("84+23", 5) == -1);
    System.out.println("Passed all tests!");
  }

  public static void testQuadrantOfIntersection() {
    System.out.print("Testing quadrantOfIntersection... ");
    assert(false); // replace this with your tests!!!
    System.out.println("Passed all tests!");
  }

  public static void testIsFibonacciNumber() {
    System.out.print("Testing isFibonacciNumber... ");
    assert(false); // replace this with your tests!!!
    System.out.println("Passed all tests!");
  }

  ////////////////////////////////////////////////////
  /// additional test methods
  ////////////////////////////////////////////////////

  public static void checkAssertsAreEnabled() {
    boolean assertsEnabled = false;
    try { assert(false); }
    catch (Throwable t) { assertsEnabled = true; }
    if (!assertsEnabled)
      throw new RuntimeException("assert statements not enabled!");
  }

  public static void testAll() {
    testDigitAt();
    testQuadrantOfIntersection();
    testIsFibonacciNumber();
  }

  ////////////////////////////////////////////////////
  /// main method
  ////////////////////////////////////////////////////

  public static void main(String[] args) {
    checkAssertsAreEnabled();
    testAll();
  }
}