// This program is flawed in several ways.  It calls update methods that
// manipulate a local copy of a variable n without updating the value of n, it
// uses the wrong if/else structures, and it has redundant code that can be
// factored.

import java.util.*;

public class BadIfReturn {
    public static void main(String[] args) {
        Scanner console = new Scanner(System.in);
        System.out.print("give me an int-> ");
        int n = console.nextInt();
        update(n);
        System.out.println("updated n = " + n);
        System.out.println();

        update2(n);
        System.out.println("updated n = " + n);
    }

    // This method updates the value of n.  It is supposed to either add one to
    // n (for negatives), reset n to 1000 (for 0), or subtract 1 from n (for
    // positives).  Because it uses the wrong if/else structure, it potentially
    // performs multiple updates
    public static void update(int n) {
        if (n < 0) {
            n++;
        }
        if (n == 0) {
            n = 1000;
        }
        if (n > 0) {
            n--;
        }
    }

    // This method performs a "special" update that either adds 42 to n (for
    // negatives) or subtracts 13 from n (for non-negatives).
    public static void update2(int n) {
        if (n < 0) {
            System.out.println("special update in progress");
            int change = 42;
            n = n + change;
            System.out.println("updated by " + change);
        } else if (n >= 0) {
            System.out.println("special update in progress");
            int change = -13;
            n = n + change;
            System.out.println("updated by " + change);
        }
    }
}