Doubt in Ques MAXXOR

Is it compulsory for us to remove a element or can we not remove even a single element.

Bcz if this was the test case -
4
7 6 5 2

then if it was compulsory to remove a element then the answer should have been 4, but if it was not compulsory then the answer would have been 6 as the xor of all these elements would have been 6.

Now i did submitted for this ques and got Correct Answer.
This is my code - https://ide.codingblocks.com/s/488720

And the answer which i was getting was 1 according to my logic which is incorrect, still it gave me AC.

So am i thinking something wrong or are the test cases weak?

yeah its optional, u can keep array as it is or u can remove one element.

probably weak test case