You would probably like one - but this is homework so you may not get anything that simple even if it is available. What you need is the tools to figure it out for yourself.I need a obvious clear explanation for this in detail thanks in advance.
You can use star-delta transformation technique.
Or as Dr. Simon Bridge pointed out,you can prove that the potential difference is zero.
For proving that the potential difference is zero, take the first half of the network. Clearly they form the wheatstone bridge condition. Thus no current flows through the vertical resistor.