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What statements are before the code you posted that prevents the posted code from executing?
What are the values of the variables that are tested?

Did you test your code? See what this statement...

Sometimes that's what happens. There could be lots of printlns and the answer to your problem will be in those print outs.
If there is one particular content of a square that gets moved, use if...

Try debugging your code by adding printlns to show the values of variables as they are changed by the program. Be sure to print out enough information do show what the code is doing and what are the...