preincrement / postincrement in java
<p>Can someome help me to understand why: </p>

<pre><code>int i=1;
int j=1;
int k=1;
int l=1;

System.out.println(i++ + i++);  
System.out.println(++j + ++j);  
System.out.println(k++ + ++k);  
System.out.println(++l + l++);
</code></pre>

<p>give:</p>

<p>3<br>
5<br>
4<br>
4  </p>
