Problem:
Score : 300 points

Problem Statement

You are playing the following game with Joisino.

Initially, you have a blank sheet of paper.

Joisino announces a number. If that number is written on the sheet, erase the number from the sheet; if not, write the number on the sheet. This process is repeated N times.

Then, you are asked a question: How many numbers are written on the sheet now?

The numbers announced by Joisino are given as A_1, ... ,A_N in the order she announces them. How many numbers will be written on the sheet at the end of the game?

Constraints

1≤N≤100000

1≤A_i≤1000000000(=10^9)

All input values are integers.

Input

Input is given from Standard Input in the following format:

N
A_1
:
A_N

Output

Print how many numbers will be written on the sheet at the end of the game.

Sample Input 1

3
6
2
6

Sample Output 1

1

The game proceeds as follows:

6 is not written on the sheet, so write 6.

2 is not written on the sheet, so write 2.

6 is written on the sheet, so erase 6.

Thus, the sheet contains only 2 in the end. The answer is 1.

Sample Input 2

4
2
5
5
2

Sample Output 2

0

It is possible that no number is written on the sheet in the end.

Sample Input 3

6
12
22
16
22
18
12

Sample Output 3

2

Solution in Common Lisp (SBCL 2.0.3) (judge verdict: Accepted)

(let* ((n (read))
    (a (make-array n :initial-element 0))
    (beforenum 0)
    (times 0)
    (ans 0))

    (dotimes (i n)
        (setf (aref a i) (read))
    )
    (sort a #'<)
    
    (setq beforenum (aref a 0))
    (setq times 1)
    (loop for i from 1 to (- n 1) do
        (if (= (aref a i) beforenum)
            (incf times)
            (progn
                (if (not (zerop (rem times 2)))
                    (incf ans)
                )
                (setq beforenum (aref a i))
                (setq times 1)
            )
        )
    )
    (if (not (zerop (rem times 2)))
        (incf ans)
    )
    (princ ans)
)