l = []
l1 = []
def cut_md(s):
    # l = []
    if s not in l:
        if s not in l1:
            l.append(s)
            l1.append(s)
    else:
        try:
             l1.remove(s)
        except:
            pass

N = int(input())
L = list(filter(cut_md, input().split()))

print(len(l1))