package PS4;

import javax.swing.*;
public class RecursionTest {
    private static int count;
    public static void main(String[] args) {
        int z;
        String input= JOptionPane.showInputDialog("Enter x");
        int x= Integer.parseInt(input);
        input= JOptionPane.showInputDialog("Enter y");
        int y= Integer.parseInt(input);
        z= MultResult(x, y);        // Swap so y is smallest, if desired
        System.out.println(x + " * " + y + " = " + z);
        System.out.println("Number of additions: " + count);
        System.exit(0);
    }
    public static int MultResult(int x, int y) {
        int result;
        boolean isNegative= false;
        count++;
  
        if (y < 0) {
            y= -y;
            isNegative= true;
        } 
        if (x== 0 || y == 0)                // x or y small enough
            result= 0;
        else if (y == 1)                    // y small enough
            result= x;
        else if (y % 2 == 0) {              // y even
            int term= MultResult(x, y/2);   // Don't do 2 recursive calls!
            result= term + term; }          // MultResult(x, y/2) + MultResult(x, y/2)
        else                                // y odd
            result= x + MultResult(x, y-1); // Add println to trace
        if (isNegative)
            result= -result;
        return result;
    }
}