Collatz.java

/*
* Eden Ghirmai
* Collatz.java
*
* Collatz Conjecture - Start with a number n > 1.
* Find the number of steps it takes to reach one using the following process: 
* If n is even, divide it by 2. If n is odd, multiply it by 3 and add 1
*/

import java.util.*;

public class Collatz {
	public static void main(String[] args) {
		Scanner console = new Scanner(System.in);
		
		System.out.println("Collatz Conjecture:");
		System.out.print("Enter a number: ");
		int num = console.nextInt();
		System.out.println("It takes " + solve(num) + " steps to reach 1 using the Collatz Conjecture,"); 
		System.out.println("beginning with the number " + num + ".");
		
	}
	
	// collatz algorithm 
	// pre-condition: n > 1
	public static int solve(int n) {
		if (n == 1) {
			return 0; 
		} else if (n % 2 == 0) {
			return 1 + solve(n / 2);
		} else {
			return 1 + solve(n * 3 + 1);
		}	 	
	}

}