N = int(input())
A = list(map(int, input().split()))
A = sorted(A)
count = 0

for i in range(N-1):
  if A[i] == A[i+1]:
    count += 1
  i += 1

if count > 0:
  print('NO')
if count == 0:
  print('YES') 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 = sorted(A) A sorted(A) sorted A count = 0 count 0 for i in range(N-1):
  if A[i] == A[i+1]:
    count += 1
  i += 1 i range(N-1) range N-1 N 1 if A[i] == A[i+1]:
    count += 1
   A[i] == A[i+1] A[i] A i A[i+1] A i+1 i 1 count += 1 count 1 i += 1 i 1 if count > 0:
  print('NO') count > 0 count 0 print('NO') print 'NO' if count == 0:
  print('YES') count == 0 count 0 print('YES') print 'YES' N = int(input()) int(input()) N count += 1 1 count count = 0 0 count A = sorted(A) sorted(A) A A = list(map(int, input().split())) list(map(int, input().split())) A i += 1 1 i
N = int(input())
A = list(map(int, input().split()))
A = sorted(A)
count = 0

for i in range(N-1):
  if A[i] == A[i+1]:
    count += 1
  i += 1

if count > 0:
  print('NO')
if count == 0:
  print('YES')