title: byte a=123; byte b=5 byte c= (byte)(a+b); gives -128. Why does this really happen?
body: <p><a href="https://www.ideone.com/gYreaO" rel="nofollow noreferrer">https://www.ideone.com/gYreaO</a> , why does this really happen? Why does it take the two's complement way to display the value?</p>
  
  <pre><code>byte a=123;
  byte b=5;
  byte c=(byte)(a+b);
  System.out.println(c);
  </code></pre>