import itertools

lgt = int(input())
dat = list(map(int, input().split()))
tmp = []
if(set(dat) == lgt):
    print(lgt)
else:
    for i in itertools.combinations(dat, 2):
        if i[0] == i[1]:
            tmp += [i[0]]
    tmp = set(tmp)
    for i in set(tmp):
        dat = list(filter(lambda a: a != i, dat))
    print(len(dat))