import collections

N=int(eval(input()))

L=list(map(int,input().split()))

a=len(L)

c=len(set(L))

if a==c:

    print('YES')

else:print('NO')
N=int(eval(input()))

L=list(map(int,input().split()))

a=len(L)

c=len(set(L))

if a==c:

    print('YES')

else:print('NO')

import collections

N = int(eval(input()))
L = list(map(int, input().split()))
a = len(L)
c = len(set(L))
if a == c:
    print("YES")
else:
    print("NO")

N = int(eval(input()))
L = list(map(int, input().split()))
a = len(L)
c = len(set(L))
if a == c:
    print("YES")
else:
    print("NO")

-import collections -