title: NullPointerException on spoj/ideone
body: <p>I'd created a program to my homework, i tried it to test on ideone.com, but i get an error:</p>
  
  <pre><code>Exception in thread "main" java.lang.NullPointerException
      at Main.main(Main.java:83)
  </code></pre>
  
  <p>for every test(in elipse workin' fine)</p>
  
  <p>line 83:</p>
  
  <pre><code> String[] val = tab.split(" ");
  </code></pre>
  
  <p>line 82: // only for informational purpose</p>
  
  <pre><code>String tab = in.readLine();
  </code></pre>
  
  <p>line 78:// only for informational purpose</p>
  
  <pre><code> BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
  </code></pre>