N = int(input())
A = tuple(map(int, input().split()))
if len(set(A)) == len(A):
    print("YES")
else:
    print("NO") N = int(input()) N int(input()) int input() input A = tuple(map(int, input().split())) A tuple(map(int, input().split())) tuple map(int, input().split()) map int input().split() ().split () input split if len(set(A)) == len(A):
    print("YES")
else:
    print("NO") len(set(A)) == len(A) len(set(A)) len set(A) set A len(A) len A print("YES") print "YES" print("NO") print "NO" A = tuple(map(int, input().split())) tuple(map(int, input().split())) A N = int(input()) int(input()) N
N = int(input())
A = tuple(map(int, input().split()))
if len(set(A)) == len(A):
    print("YES")
else:
    print("NO")