n = int(input())
a = list(map(int, input().split()))
a.sort()
pd = True
for i in range(n-1):
  if a[i] == a[i+1]:
    pd = False
if pd: print('YES')
else: print('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 a.sort() a.sort a sort pd = True pd True for i in range(n-1):
  if a[i] == a[i+1]:
    pd = False i range(n-1) range n-1 n 1 if a[i] == a[i+1]:
    pd = False a[i] == a[i+1] a[i] a i a[i+1] a i+1 i 1 pd = False pd False if pd: print('YES')
else: print('NO') pd n = int(input()) int(input()) n a = list(map(int, input().split())) list(map(int, input().split())) a pd = True True pd pd = False False pd
n = int(input())
a = list(map(int, input().split()))
a.sort()
pd = True
for i in range(n-1):
  if a[i] == a[i+1]:
    pd = False
if pd: print('YES')
else: print('NO')