n = int(input())
a = input().split()
a = [int(i) for i in a]
a.sort()
flg = "YES"
for i in range(n-1):
    if (a[i] == a[i+1]):
        flg = 'NO'
        break
print(flg) n = int(input()) n int(input()) int input() input a = input().split() a input().split() ().split () input split int(i) for i in a for i in a i a for i in a int(i) int i a = [int(i) for i in a] a [int(i) for i in a] a.sort() a.sort a sort flg = "YES" flg "YES" for i in range(n-1):
    if (a[i] == a[i+1]):
        flg = 'NO'
        break i range(n-1) range n-1 n 1 if (a[i] == a[i+1]):
        flg = 'NO'
        break a[i] == a[i+1] a[i] a i a[i+1] a i+1 i 1 flg = 'NO' flg 'NO' break print(flg) print flg flg = "YES" "YES" flg n = int(input()) int(input()) n a = [int(i) for i in a] [int(i) for i in a] a flg = 'NO' 'NO' flg a = input().split() input().split() a
n = int(input())
a = input().split()
a = [int(i) for i in a]
a.sort()
flg = "YES"
for i in range(n-1):
    if (a[i] == a[i+1]):
        flg = 'NO'
        break
print(flg)