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In the findFirst method, the loop's condition repeatedly asks the flies collection how many files it is storing. Does the value returned by size vary from one check to the next? If you think the answer is no, then rewrite the method so that the number of files is determined only once and stored in a local variable prior to execution of the loop. Then use the local variable in the loop's condition rather than the call to size. Check that this version gives the same results. If you have problems completing this exercise, try using the debugger to see where things are going wrong.
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