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