scope of local variable in enhanced for-loop

Question

I have a rather simple question about variable scope.

I am familiar with the Enhanced For-Loops but I do not get why I should declare a new variable to keep each el

Answer 1

The int i in the program is visible to the for loop and maybe other for loops beneath it (if present) under the same scope. But the i inside the for(int i : ar) is local to the for loop. Hence ending once the execution of loop is over. Thats the syntax defined for foreach loop that "you have to use a variable with scope limited to the loop".

So why I should declare this new variable? After all i is accessible inside the for loop. I did not want to use any previous value of i, just did not want to declare a new variable. (I guessed for other iterable items it might be faster using the same variable).

Why would there be any considerable performance benefit if you use the same variable tiny primitive variable over and over versus creating a one only when needed and which gets destroyed after loop ends.