n = int(input())
P = list(map(int,input().split()))


S={}
ans="YES"
for p in P:
    if p in S:
        ans = "NO"
        break
    else:
        S[p]=1

print(ans)
 n = int(input()) n int(input()) int input() input P = list(map(int,input().split())) P list(map(int,input().split())) list map(int,input().split()) map int input().split() ().split () input split S={} S {} ans="YES" ans "YES" for p in P:
    if p in S:
        ans = "NO"
        break
    else:
        S[p]=1 p P if p in S:
        ans = "NO"
        break
    else:
        S[p]=1 p in S p S ans = "NO" ans "NO" break S[p]=1 S[p] S p 1 print(ans) print ans ans="YES" "YES" ans ans = "NO" "NO" ans S={} {} S P = list(map(int,input().split())) list(map(int,input().split())) P n = int(input()) int(input()) n
n = int(input())
P = list(map(int,input().split()))


S={}
ans="YES"
for p in P:
    if p in S:
        ans = "NO"
        break
    else:
        S[p]=1

print(ans)

