Thread: If/else statement working incorrectly...

Hi this is a towers of hanoi puzzle program. Right now I am having trouble with getting the program to solve for 3 discs if when prompted 'Enter the number of discs' is blank (i.e. enter key is hit without inputting any integer value).

My if/else statement inside my hanoi method is where I think the problem is. I commented out where I think the problem is. How do I get the program to just solve for just 3 discs if nothing is input when prompted for 'Enter the number of discs'?

Code:

import java.util.Scanner;
 
public class TowerOfHanoi4 {
	static int moves = 0;
	static boolean displayMoves = false;
 
	public static void main(String[] args) {
 
		System.out.println("Enter the Number of Discs : ");
		Scanner scanner = new Scanner(System.in);
		int iHeight = scanner.nextInt();
		char source = 'S', auxiliary = 'D', destination = 'A'; // name poles or
																// 'Needles'
      // int blank = null;
 
		System.out.println("Press 'v' or 'V' for a list of moves");
		Scanner show = new Scanner(System.in);
		String c = show.next();
		displayMoves = c.equalsIgnoreCase("v");
 
 
		hanoi(iHeight, source, destination, auxiliary);
		System.out.println(" Total Moves : " + moves);
	}
 
	static void hanoi(int height, char source, char destination, char auxiliary) {
		if (height >= 1) {
			hanoi(height - 1, source, auxiliary, destination);
			if (displayMoves) {
				System.out.println(" Move disc from needle " + source + " to "
						+ destination);
			}
			moves++;
			hanoi(height - 1, auxiliary, destination, source);
		}
//       else (height = 3) {                                  //I think the problem
//          hanoi(height - 1, source, auxiliary, destination);//Lies with this
//          moves++;                                          //else
//          hanoi(height - 1, auxiliary, destination, source);//statement         
//       }   
	}
}

else (height = 3)

This is a syntax error for two reasons. It will not compile.

The correct structure of an if /else if / else statement is:

if (height >= 1) {
     // do something
 
} else if (height == 3) {
     //  note that it is else if, 
     //  also note the double equals (==).  A single equals assigns a variable,  a double equals test for equality.
 
}  else {
    // do something if the other two aren't true
 
}

But there is yet another problem here, an issue with the logic. If height >= 1 it will execute that branch of the if statement. Since 3 >= 1 it will never reach that part of the code.

cool thanks! got it working