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?
import collections

def test():
    n = int(input())
    a = [int(input()) for i in range(n)]
    b = collections.Counter(a)
    print(b)
    ans = 0
    for i in b.values():
        if i % 2 != 0:
            ans += 1
    print(ans)


if __name__ == "__main__":
    test()

import collections

def test():
    n = int(input())
    a = [int(input()) for i in range(n)]
    b = collections.Counter(a)
    ans = 0
    for i in b.values():
        if i % 2 != 0:
            ans += 1
    print(ans)


if __name__ == "__main__":
    test()
