n = int(input())
lst = list(map(int,input().split()))
x = len(lst)
lst = list(set(lst))
y = len(lst)

if (x == y):
    print("YES")
else:
    print("NO") n = int(input()) n int(input()) int input() input lst = list(map(int,input().split())) lst list(map(int,input().split())) list map(int,input().split()) map int input().split() ().split () input split x = len(lst) x len(lst) len lst lst = list(set(lst)) lst list(set(lst)) list set(lst) set lst y = len(lst) y len(lst) len lst if (x == y):
    print("YES")
else:
    print("NO") x == y x y print("YES") print "YES" print("NO") print "NO" lst = list(map(int,input().split())) list(map(int,input().split())) lst x = len(lst) len(lst) x y = len(lst) len(lst) y n = int(input()) int(input()) n lst = list(set(lst)) list(set(lst)) lst
n = int(input())
lst = list(map(int,input().split()))
x = len(lst)
lst = list(set(lst))
y = len(lst)

if (x == y):
    print("YES")
else:
    print("NO")
