title: javac Main.java is not working in cmd
body: <p>I have 3 class as below:</p>
  
  <p><strong>First:</strong></p>
  
  <pre><code>package com.coban.menu;
  
  public class Square {
  
      public static double Perimeter(double x) {
          return 4 * x;
      }
  
  }
  </code></pre>
  
  <p><strong>Second:</strong></p>
  
  <pre><code>package com.coban.menu;
  
  public class Circle {
      public static final double PI = 3.14;
  
      public static double Acreage(double x) {
          return PI * x * x;
      }
  }
  </code></pre>
  
  <p><strong>Third:</strong></p>
  
  <pre><code>package com.coban.main;
  
  import java.util.Scanner;
  
  import com.coban.menu.Circle;
  import com.coban.menu.Square;
  
  public class Main {
  
      public static void main(String[] args) {
          // TODO Auto-generated method stub
  
          Scanner scan = new Scanner(System.in);
  
          System.out.println("Selection");
          System.out.println("1 - Square perimeter");
          System.out.println("2 - Circle Acreage");
  
          int x = scan.nextInt();
  
          switch (x) {
          case 1:
              System.out.println("Input edge length:");
              float chieuDaiCanh = scan.nextFloat();
              System.out.println("Square perimeter: "+Square.Perimeter(chieuDaiCanh));
              break;
          case 2:
              System.out.println("Input radius:");
              float banKinh = scan.nextFloat();
              System.out.println("Circle Acreage: "+Circle.Acreage(banKinh));
              break;
  
          default:
              System.out.println("M nhap cai lol gi the?");
              break;
          }
      }
  
  }
  </code></pre>
  
  <p>The program is working well in IDE.
  Why <code>&gt;javac Main.java</code> is not working in cmd? </p>
  
  <p>Err1:</p>
  
  <pre><code>com.coban.menu pakage does not exist
  </code></pre>
  
  <p>Err2:</p>
  
  <pre><code>cannot find a symbol in :
   System.out.println("Square perimeter: "+Square.Perimeter(chieuDaiCanh));
   System.out.println("Circle Acreage: "+Circle.Acreage(banKinh));
  </code></pre>
  
  <p>Somebody help me!</p>