This type of problem in a few lines I'm not sure, can make a little explanation?
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CodePudding user response:
Arr4 arr5 is an Integer array, because when you declare a variable specified type is Integer []Arrlist type is the List (a set), point to the ArrayList object, the object to save the 1, 2, 3 three plastic objects, the three arr4 conversion and plastic objects come from
Then arrlist added during the three plastic objects, the three arr5 conversion and plastic objects come from