test.java

/**
 * Created by RupGautam on 2/22/17.
 */

import java.util.Random;
import java.util.Scanner;

/**
 * Copyright ${COPYRIGHT}.
 */
public class test {

  public static void main(String[] args) {
    int[] a = new int[1000];
    int old_n = 0, n = 0;
    int step = 0;

    a[n++] = 25;
    int goal = 11;
    boolean found = a[0] == goal;

    while (!found) {
      step++;
      System.out.print("" + step + " steps: ");
      int start_n = old_n;
      old_n = n;
      for (int i = start_n; i < old_n; i++)
        for (int opt = 0; opt < 2; opt++) {
          int new_a = -1;
          switch (opt) {
            case 0:
              if (a[i] % 2 == 0)
                new_a = a[i] / 2;
              break;
            case 1:
              new_a = a[i] + 3;
          }
          if (new_a < 0)
            continue;

          if (new_a == goal)
            found = true;
          int j = 0;
          while (j < n && a[j] != new_a)
            j++;
          if (j >= n) {
            System.out.print(" " + new_a);
            a[n++] = new_a;
          }
        }
      System.out.println();
    }
  }
}