n = int(input())
a = list(map(int,input().split()))
print("YES" if len(set(a))==len(a) else "NO") n = int(input()) n int(input()) int input() input a = list(map(int,input().split())) a list(map(int,input().split())) list map(int,input().split()) map int input().split() ().split () input split print("YES" if len(set(a))==len(a) else "NO") print "YES" if len(set(a))==len(a) else "NO" len(set(a))==len(a) len(set(a)) len set(a) set a len(a) len a "YES" "NO" a = list(map(int,input().split())) list(map(int,input().split())) a n = int(input()) int(input()) n
n = int(input())
a = list(map(int,input().split()))
print("YES" if len(set(a))==len(a) else "NO")