N = int(raw_input())
input = sorted(raw_input().strip().split())
cnt = 0
while input:
    if len(input) == 0:
        break
    elif len(input) == 1:
        cnt += 1
        break
    else:
        top = input.pop(0)
        nxt = input[0]
        if top == nxt:
            while index.remove(top):
                pass
        else:
            cnt += 1
        
print cnt