peterverebics/CodeNet_Python_118 huggingface dataset:
n=int(input())
A=[int(i) for i in input().split()]
if len(set(A))==n:
    print("YES")
else:
    print("NO")
n = input()
a = map(int, raw_input().strip().split())
s = list(set(a))

if len(s) != n:
    print "NO"
else:
    print "YES"
def solve():
    N = int(input())
    A = [int(i) for i in input().split()]

    set_A = set([])
    for num in A:
        if num in set_A:
            print('NO')
            return
        set_A.add(num)
    print('YES')

if __name__ == "__main__":
    solve()
n = int(input())
a_set = set(map(int, input().split()))
if len(a_set) == n:
  print("YES")
else:
  print("NO")
n = int(input())
listed = list(map(int,input().split()))

length2 = len(set(listed))

if n == length2:
    print('YES')
else:
    print('NO')
n=int(input())
a=set(map(int,input().split()))
if n==len(a):
  print("YES")
else:
  print("NO")
N = int(input())
L_a = [int(s) for s in input().rstrip().split(' ')]
l_a = set(L_a)
if len(l_a) == len(L_a):
  print("YES")
else:
  print("NO")
N = int(input())
*l, = map(int, input().split())
print("YES" if len(l)==len(set(l)) else "NO")
n = int(input())
a = [int(x) for x in input().split()]
a = sorted(a)
for i in range(n-1):
    if a[i] == a[i+1]:
        print('NO')
        exit(0)
print('YES')
n=int(input())
A=set(map(int, input().split()))
if n==len(A):
    print('YES')
else:
    print('NO')
import sys
def input(): return sys.stdin.readline().rstrip()

def main():
    n = int(input())
    A = tuple(map(int, input().split()))
    if len(set(A)) == len(A):
        print('YES')
    else:
        print('NO')


if __name__ == '__main__':
    main()
n = int(input())
a = list(map(int, input().split()))

set_a = list(set(a))

if( len(a) == len(set_a)):
    print('YES')
else:
    print('NO')
def resolve():
    N = int(input())
    A = list(map(int, input().split()))
    if len(set(A)) == len(A):
        print('YES')
    else:
        print('NO')
resolve()
from collections import Counter
import sys
N = int(input())
A = [int(x) for x in input().split()]

C = dict(Counter(A))
for a in C:
    if C[a] > 1:
        print('NO')
        sys.exit()
print('YES')
def A():
    temp = input().split()
    S = temp[0]
    T = temp[1]
    temp = [int(i) for i in input().split()]
    A = temp[0]
    B = temp[1]
    U = input()
    if U == S:
        print(A-1, B)
    else:
        print(A, B-1)

def B():
    print('x'*len(input()))

def C():
    N = int(input())
    A = [int(i) for i in input().split()]
    if N > len(set(A)):
        print('NO')
    else:
        print('YES')
        
C()
import collections
N = int(input())
l = list(map(int,input().split()))

c = collections.Counter(l)
if c.most_common()[0][1] > 1:
    print('NO')
else:
    print('YES')
n = int(input())
a = list(map(int, input().split()))
sa = set(a)
if len(a) == len(sa):
  print("YES")
else:
  print("NO")
n = int(input())
A = [i for i in map(int,input().split())]
A_set = set(A)
if len(A) == len(A_set):
  print("YES")
else:
  print("NO")
import sys
n = int(input())
a = sorted(list(map(lambda x: int(x),input().split())))
for i in range(n - 1):
    if a[i] == a[i+1] :
        print('NO')
        sys.exit()
print('YES')
n = int(input())
A = list(map(int,input().split()))

if len(A) != len(set(A)):
  print("NO")
else:
  print("YES")
n=int(input())
a=list(map(int,input().split()))
b=set(a)
print("YES" if n == len(b) else "NO")
A=int(input())
B=list(map(int,input().split()))
C=len(set(B))
if A==C:
    print('YES')
else:
    print('NO')
n=int(input())
a=list(map(int,input().split()))
dic={}
out=0

for num in a:
    if num in dic.keys():
        out=1
        break
    else:
        dic[num]=1

if out==0:
    print('YES')
else:
    print('NO')
n = int(input())
a = map(int,input().split())

if len(set(a)) == n:
  print("YES")
else:
  print("NO")
'''
Sample Input 1

5
2 6 1 4 5
Sample Output 1

YES
'''
lens = int(input())
arrs = [int(x) for x in input().split()]
print(["NO", "YES"][len(arrs) == len(set(arrs))])
from collections import Counter

N = input()
A = map(int, input().split())

ans = Counter(A)
max_value = max(ans.values())

if max_value == 1:
    print('YES')
else:
    print('NO')
import collections

_ = input()
_list = input()
 
num_list = _list.split(' ')
 
c = collections.Counter(num_list)
if c.most_common()[0][1] > 1:
  print('NO')
else:
  print('YES')
N = int(input())
A_list = list(map(int,input().split()))
A_set = set(A_list)

if len(A_list) == len(A_set):
    print("YES")
else:
    print("NO")
def main():
    N = int(input())
    A = [int(i) for i in input().split()]
    A.sort()
    for i in range(N-1):
        if A[i] == A[i+1]:
            return print("NO")
    print("YES")


if __name__ == '__main__':
    main()
import sys

def II(): return int(input())
def MI(): return map(int,input().split())
def LI(): return list(map(int,input().split()))
def TI(): return tuple(map(int,input().split()))
def RN(N): return [input().strip() for i in range(N)]


def main():
    N = II()
    A = LI()
    numa = len(set(A))
    #print(numa)
        
    if numa == N:
        print("YES")
    else:
        print("NO")


if __name__ == "__main__":
	main()
print('YES' if int(input())==len(set(input().split())) else 'NO')
N = int(input())
A = list(map(int, input().split()))
B = set(A)
if len(A)==len(B):
    print('YES')
else:
    print('NO')
def checker(arr):
  d = {}
  for x in arr:
    if x not in d:
      d[x] = 1
    else:
      return "NO"
  return "YES"

n = int(input())
arr = list(map(int, input().split()))
print(checker(arr))
MOD = 1000000007
INF = float("inf")

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

h = set()
for elem in A:
    if elem in h:
        print("NO")
        exit()
    h.add(elem)

print("YES")
n = int(input())
a = set(map(int, input().split()))
print('YES' if len(a) == n else 'NO')
n = int(input())
A = list(map(int,input().split()))

if n == len(set(A)):
  print('YES')
else:
  print('NO')
n=int(input())
a=list(map(int,input().split()))

b=list(set(a))
if len(a)==len(b):
    print("YES")
else:
    print("NO")
N =int(input())

d = {}

for word in input().split():
    if word in d:
        print("NO")
        exit()
    else:
        d[word] = 1

print("YES")
a = int(input())
ar = list(map(int,input().split(" ")))
if len(set(ar)) == a:
    print("YES")
else:
    print("NO")
N=int(input())
n=list(map(int,input().split()))
A=len(n)
m=set(n)
B=len(m)
if A==B:
    print("YES")
else:
    print("NO")
n=int(input())
l=input().split()
l.sort()
flag=1
for i in range(n-1):
  if l[i]==l[i+1]:flag=0
if flag==1:print("YES")
else:print("NO")
def resolve():
    N=int(input())
    S=len(set(map(int,input().split())))
    print("YES" if N==S else "NO")

if __name__ == "__main__":
    resolve()
n=int(input())
ls=list(map(int,input().split()))
m=len(ls)
print("YES" if len(set(ls))==m else "NO")
N = int(input())
A = list(map(int, input().split(" ")))
A.sort()
same = False
for i in range(N - 1):
  if A[i] == A[i + 1]:
    same |= True
print('NO' if same else 'YES')
import collections
n = int(input())
A = [int(i) for i in input().split()]
ans = collections.Counter(A)
ans = list(ans)
if len(ans)==n:
  print('YES')
else:
  print('NO')
N = int(input())
A = {i for i in input().split()}
print("YES" if N==len(A) else "NO")
import sys
N = int(input())
A = list(map(int,input().split()))
res = dict()
for key in A:
  if key not in res:
    res[key] = 0
  res[key] += 1
  if res[key] >= 2:
    print('NO')
    sys.exit(0)
print('YES')
N = int(input())
A = []
A = input().split()
A = [int(i) for i in A]

#print('N = ', N)
#print('A = ', A)

A.sort()
#print('sortA = ', A)

count = 0

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

if count > 0:
  print('NO')
else:
  print('YES')
n = int(input())
#a,b = map(int,input().split())
a_L = list(map(int,input().split()))
#print(a_L)
if len(a_L) == len(set(a_L)):
    print("YES")
else:
    print("NO")
N = int(input())
A = input().split()
if N == len(list(set(A))):
  print('YES')
else:
  print('NO')
N = int(input())
L = list(map(int,input().split()))
M = set(L)
if len(L) == len(M):
    print('YES')
else:
    print('NO')
n = int(input())

a = list(map(int,input().split()))

a.sort()

p = 0
for i in range(n-1):
    if a[i] == a[i+1]:
        p += 1


if p == 0:
    print("YES")
else:
    print("NO")
n = int(input())
a = list(map(int,input().split()))

if len(a) != len(set(a)):
    print("NO")
else:
    print("YES")
n = int(input())

# 被りの要素が削除される
a = set(input().split())
print('YES' if len(a) == n else 'NO')
N=int(input())
A=input().split()
A = [int(a) for a in A]
 
A.sort()

count=True

for i in range(N-1):
    if A[i]==A[i+1]:
        count=False
        break
    
if count:
    print("YES")
else:
    print("NO")
N=int(input())
A=list(map(int,input().split()))

if len(A)==len(set(A)):
    print("YES")
else:
    print("NO")
n = int(input())
a_ = list(map(int,input().split()))

import collections
cnt = list(collections.Counter(a_))

print('YES' if len(cnt) == n else 'NO')
n = int(input())
a = sorted([int(_) for _ in input().split()])

flag = 0
for i in range(n-1):
    if a[i] == a[i+1]:
        flag = 1
        break

if flag:
    print('NO')
else:
    print('YES')
N = int(input())
L = list(map(int, input().split()))
if len(set(L)) == len(L):
    print("YES")
else:
    print("NO")
n = int(input())
a = list(map(int, input().split()))
seta = set(a)
if len(a)==len(seta):
  print("YES")
else:
  print("NO")
n=int(input())
a=list(map(int,input().split()))

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

def dup(seq):
    return len(seq) != len(set(seq))

if(dup(li)): 
    print("NO")
else:
     print("YES")
n = int(input())
l = list(map(int,input().split()))
l1 = set(l)
if len(l) == len(l1):
    print("YES")
else:
    print("NO")
n = int(input())
a = list(map(int,input().split()))
if len(set(a)) == len(a):
    print("YES")
else:
    print("NO")
n=int(input())
A=set(map(int,input().split()))
print('YES' if len(A)==n else 'NO')
def main():
    N = int(input())
    A = list(map(int,input().split()))
    if len(A) == len(set(A)):
        print("YES")
    else:
        print("NO")

if __name__ == '__main__':
    main()
N = int(input())
val = list(input().split())
               
if len(val) == len(set(val)):
    print('YES')
else:
    print('NO')
import collections

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

cs = collections.Counter(A)
mcs = cs.most_common()
cnt = mcs[0][1]
if cnt == 1:
    print('YES')
else:
    print('NO')
def main(list_A):

    list_A = sorted(list_A)
    prev_A = 0
    for A in list_A:
        if A == prev_A:
            return "NO"
        else:
            prev_A = A
    else: return "YES"


if __name__ == "__main__":

    N      = int(input())
    list_A = list(map(int, input().split(' ')))

    answer = main(list_A)
    print(answer)
n = int(input())
a = list(map(int, input().split()))
d = dict()
for i in range(n):
    d.setdefault(a[i])
if len(d) != n :
    print("NO")
else:
    print("YES")
n=int(input())
l=list(map(int,input().split()))
s=set(l)
if len(s)==n:
  print("YES")
else:
  print("NO")
n = input()
a = list(map(int,input().split()))
if len(set(a)) == len(a):
  print("YES")
elif len(set(a)) != len(a):
  print("NO")
n=int(input())
a=list(map(int,input().split()))
ans="YES"
a.sort()
mae=0
for i in a:
  if i==mae:
    ans="NO"
    break
  else:
    mae=i
print(ans)
n = int(input())

a = list(map(int,input().split()))
if n ==len(set(a)):
    print("YES")
else:
    print("NO")
n = int(input())
a = list(map(int, input().split()))

if n == len(set(a)):
  print("YES")
else:
  print("NO")
import collections
n=int(input())
a=collections.Counter(list(map(int, input().split())))
if len(a)==n: print('YES')
else: print('NO')
n = int(input())
arr = input().split()
print("YES" if len(arr) == len(set(arr)) else "NO")
S = input()
A = list(map(int, input().split()))
A.sort()
Y=0
Z=0
while Z < int(S)-1:
  if int(A[Z]) - int(A[Z+1]) == 0:
    print("NO")
    Y=1
    break
  else:
    Z = Z+1
    continue
if not Y ==1:
  print("YES")
n = int(input())
li = list(map(int,input().split()))
a = len(li)
b = len(set(li))
if a==b:
    print('YES')
else:
    print('NO')
N = int(input())
A = input().split()
for i in range (N) :
    A[i] = int(A[i])

A = sorted(A)
fl = True

for i in range (1 , N) :
    if (A[i - 1] == A[i]) :
        fl = False
        break

print ('YES' if fl else 'NO')
def main():
    N = int(input())
    A = list(map(int, input().split()))
    if len(A) == len(set(A)):
        print('YES')
    else:
        print('NO')

if __name__ == "__main__":
    main()
n = int(input())
a = [int(_a) for _a in input().split()]

set_a = set(a)
if len(set_a) == len(a):
    print("YES")
else:
    print("NO")
N = int(input())
A = list(map(int, input().split()))

s = set(A)
if len(s) == N:
    print("YES")
else:
    print("NO")
#!/usr/bin/env python

from collections import deque, defaultdict
import itertools as ite
import sys
import math
from decimal import *

sys.setrecursionlimit(1000000)

INF = 10 ** 18
MOD = 10 ** 9 + 7

N = input()
A = map(int, raw_input().split())
A = sorted(A)
for i in range(N):
    if A[i - 1] == A[i]:
        print "NO"
        exit()
print "YES"
n = int(input())
a = list(map(int, input().split()))
import collections
a_c = collections.Counter(a)
if sum(a_c.values()) == len(a_c.values()):
    print('YES')
else:
    print('NO')
n = int(input())
a = list(map(int, input().split()))
if len(a) == len(set(a)):print('YES')
else: print('NO')
n=int(input())
arr=list(map(int,input().split()))
s=set(arr)
if(len(s)==len(arr)):
  print("YES")
else:
  print("NO")
n = int(input())
a = [int(x) for x in input().split()]

a = sorted(a)

t = a[0]

for i in range(1,n):
    if t == a[i]:
        print('NO')
        exit()
    else:
        t = a[i]

print('YES')
n=int(input())
a=list(map(int,input().split()))
l=set(a)
if len(l)==len(a):
  print("YES")
else:
  print("NO")
n=input()
as_=list(map(int,input().split()))
print('YES' if len(as_)==len(set(as_)) else 'NO')
N = int(input())
A = set(map(int, input().split()))
print ("YES" if len(A)==N else "NO")
N = int(input())
A = list(input().split())
A.sort()
for i in range(N-1):
    if A[i]==A[i+1]:
        print('NO')
        exit()
print('YES')
n = int(input())
a = set(map(int, input().split()))

if len(a) < n:
    print("NO")
if len(a) == n:
    print("YES")
N=int(input())
A=[""]*N

A=list(map(int,input().split()))

if len(set(A))==len(A):
    print("YES")
else:
    print("NO")
N=int(input())

A=list(map(int,input().split()))

S=set()
for i in A:
    S.add(i)

if len(S)==len(A):
    print("YES")
else:
    print("NO")
N=int(input())
A=set(list(map(int, input().split())))
if N==len(A):
    print("YES")
else:
    print("NO")
N = int(input())
An = list(map(int, input().split()))

if len(An) == len(set(An)):
    print('YES')
else:
    print('NO')
from sys import stdin, setrecursionlimit


def main():
    n = int(stdin.readline())
    a = list(map(int, stdin.readline().split()))

    if n == len(set(a)):
        print('YES')
    else:
        print('NO')


if __name__ == "__main__":
    setrecursionlimit(10000)
    main()
from collections import Counter
N = int(input())
A = list(map(int, input().split()))
cnt = Counter(A)
print('YES' if len(cnt) == N else 'NO')
n=int(input())
a=set(map(int,input().split()))
if len(list(a)) < n:
  print('NO')
else:
  print('YES')
from collections import Counter

N=int(input())
int_s = list(map(int,input().split()))

c=Counter(int_s)

product =1
for i in list(c.values()):
    product*=i

if product==1:
    print('YES')
else:
    print('NO')
n = int(input())
a = set()
for i in input().split():
  a.add(i)
print("YES" if len(a) == n else "NO")
n = int(input())
a = [int(num) for num in input().split()]
a.sort()
ans = "YES"
for i in range(n-1):
    if a[i] == a[i+1]:
        ans = "NO"
print(ans)
n = int(input())
l = list(map(int, input().split()))
if len(l)==len(set(l)):
    print("YES")
else:
    print("NO")
N = int(input())
A = list(map(int,input().split()))
num_dict = {}
for i in A:
    if i in num_dict.keys():
        num_dict[i] += 1
    else:
        num_dict[i] = 1
ok = 0
for i in num_dict.values():
    if i >= 2:
        print('NO')
        ok = 1
        break
if ok == 0:
    print('YES')
N = int(input())
A = [int(i) for i in input().split()]

A_dict = {}
ans = "YES"

for i in range(len(A)):
  if A[i] not in A_dict:
    A_dict[A[i]] = 1
  else:
    ans = "NO"
    break

print(ans)
N = int(input())
A = list(map(int, input().split()))
if len(A) == len(set(A)):
    print("YES")
else:
    print("NO")
S = set()
input()
for a in map(int, input().split()):
  if a in S:
    print("NO")
    exit()
  else:
    S.add(a)
print("YES")
n = int(input())
List = list(map(int, input().split()))

if len(set(List)) == len(List):
    print("YES")
else:
    print("NO")
n = int(input())
A = list(map(int, input().split()))
if len(list(set(A))) == n:
  print("YES")
else:
  print("NO")
n=int(input())
x=list(map(int,input().split()))
x.sort()
v=x[0]
y=True
for i in range(1,len(x)):
  if v==x[i]:
    y=False
    break
  else:
    v=x[i]
    
if y==True:
  print("YES")
else:
  print("NO")
N=int(input())
A=list(map(int,input().split()))

A_set=set(A)
if len(A_set)==N:
    print('YES')
else:
    print('NO')
l=int(input())
list = list(map(int, input().split()))

def has_duplicates(seq):
    return len(seq) != len(set(seq))

r=has_duplicates(list)

if(str(r)=="False"):
  print("YES")
else:
  print("NO")
n = input()
a = list(input().split())

b = set(a)

if len(a) == len(b):
  print("YES")
else:
  print("NO")
input = raw_input
n = int(input())
As = set(map(int, input().split(" ")))

nn = len(As)

if nn == n:
    out = "YES"
else:
    out = "NO"
print(out)
n=int(input())
a=list(map(int,input().split()))
a.sort()
flag=True
for i in range(len(a)-1):
  if a[i]==a[i+1]:
    flag=False
if flag:
  print("YES")
else:
  print("NO")
l1 = input()
l1 = input().split()
l2 = set(l1)
if len(l1) == len(l2):
  print("YES")
else:
  print("NO")
_ = input()
nums = list(input().split())

nums_set = set(nums)
print('YES' if len(nums) == len(nums_set) else 'NO')
n=input().split()
li=[]
a=list(map(int,input().split()))

p=set(a)

if len(a)==len(p):
    print("YES")
else:
    print("NO")
def main():
    N = int(input())
    a = [int(x) for x in input().split()]
    if len(a) == len(set(a)):
        print("YES")
    else:
        print("NO")


if __name__ == '__main__':
    main()
N, *X = map(int, open(0).read().split())

if N == len(set(X)):
    print("YES")
else:
	print("NO")
N = int(input())
A = set(map(int,input().split()))
if len(A) == N:
    print("YES")
else:
    print("NO")
n=int(input())
a=list(map(int,input().split()))

if len(a) == len(set(a)):
    print('YES')
else:
    print('NO')
N = int(input())
A = list(map(int, input().split()))

def check(seq):
    if len(seq) != len(set(seq)):
        return "NO"
    else:
        return "YES"

print(check(A))
N = input()
A = input().split()
n = len(A)
n_temp = len(set(A))

if n != n_temp:
  print("NO")
else:
  print("YES")
N = int(input())
A = list(map(int, input().split()))
A.sort()

for i in range(N-1):
  if A[i] == A[i+1]:
    print('NO')
    exit()
  else:
    pass
print('YES')
N=int(input())
A=list(map(int,input().split()))
if len(set(A))==N:
    print('YES')
else:
    print('NO')
def resolve_C():
    n = input()
    s = input().split()
    if len(s) == len(set(s)):
        print("YES")
    else:
        print("NO")
resolve_C()
N=int(input())
As=[int(i) for i in input().split()]

if len(list(set(As)))!=len(As):
    print("NO")
else:
    print("YES")
n = int(input())
arr = list(map(int,input().split()))

arrset = set(arr)

if len(arr) == len(arrset):
    print("YES")
else:
    print("NO")
n = int(input())
m = list(map(int,input().split()))
if len(set(m)) == len(m):
    print("YES")
else:
    print("NO")
from collections import Counter
n = int(input())
a = list(map(int,input().split()))
acount = Counter(a)
if n == (len(list(acount.keys()))):
         print("YES")
else:
         print("NO")
n = int(input())
a = list(map(int,input().split()))

if len(set(a)) == n:
  print('YES')
else:
  print('NO')
from collections import Counter
N = int(input())
print("YES" if len(Counter(list(map(int,input().split()))).keys())==N else "NO")
N = int(input())

A = list(map(int,input().split()))
Ai = set(A)
ans = "NO"
if len(A) == len(Ai):
    ans = "YES"
else:
    ans = "NO"
print(ans)
n=int(input())
a=[int(x) for x in input().split()]
b=set(a)
l=len(b)
if l==n:
  print("YES")
else:
  print("NO")
# -*- coding: utf-8 -*-

N = int(input())
A = list(input().split())
s = set()
for a in A:
    if a in s:
        print("NO")
        exit()
    s.add(a)
print("YES")
from collections import Counter

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

counter = Counter(A)
if max(counter.values()) == 1:
    print("YES")
else:
    print("NO")
import sys
n = int(input())
a = [int(a) for a in input().split()]

done = {}
flag = 0
for i in range(n):
  try:
    if done[a[i]] > 0:
      flag = 1
    done[a[i]] = 1
  except:
    done[a[i]] = 1

if flag:
  print('NO')
else:
  print('YES')
#C - Distinct or Not
#最初の要素数(n)と重複を取り除いた後の要素数(after_set)を比較する

#操作前の要素数(n)とリスト(numbers)
n = int(input())
numbers = list(map(int,input().split()))

#重複を取り除く(set()を使う)
unique_numbers = list(set(numbers))
after_set = len(unique_numbers)

#一致していれば'YES'、一致していなければ'NO'を出力
if(n == after_set):
    print('YES')
else:
    print('NO')
n = int(input())
a = list(map(int,input().split()))

a = set(a)
if len(a) == n:
    print("YES")
else:
    print("NO")
N=int(input())
A=list(map(int,input().split()))

A.sort()
flag=True
for i in range(0,N-1):
    if A[i]==A[i+1]:
        flag=False
        break;
if flag:
    print("YES")
else:
    print("NO")
n = int(input())
a = map(int, input().split())

l = set(a)
if n == len(l):
    print('YES')
else:
    print('NO')
N = int(input())
A = list(map(int, input().split()))
S = set(A)
if len(S)==len(A):
    print("YES")
else:
    print("NO")
import sys
n = int(sys.stdin.readline())
a = list(map(int,sys.stdin.readline().split()))
b = {}
d = True
for x in a:
  if x in b:
    d = False
    print("NO")
    break
  else:
    b[x] = 1

if d:
  print("YES")
# -*- coding: utf-8 -*-
N = int(input())
A = list(map(int, input().split()))
A = sorted(A)

for i in range(1, N):
  if A[i-1] == A[i]:
    print("NO")
    exit()
print("YES")
n = int(input())
lst = list(map(int, input().split()))

def has_duplicates(seq):
    return len(seq) != len(set(seq))

if has_duplicates(lst)==True:
    print("NO")
else:
    print("YES")
#C
from collections import Counter
N=int(input())
A=[int(x) for x in input().split()]

A_C=Counter(A)

flag=True
for i,v in A_C.items():
    if v!=1:
        flag=False
        break
if flag:
    print("YES")
else:
    print("NO")
N = int(input())
A = list(map(int, input().split()))

answer = 'YES'
AA = sorted(A)
for i in range(N - 1):
    if AA[i] == AA[i + 1]:
        answer = 'NO'
        break

print(answer)
# C - Distinct or Not
# https://atcoder.jp/contests/abc154/tasks/abc154_c

num = int(input())
p = list(map(int, input().split()))
list.sort(p)

ret = "YES"
for i in range(num-1):
    if p[i] == p[i+1]:
        ret = "NO"
        break

print("{}".format(ret))
N=int(input())
A=list(map(int, input().split()))
a=set(A)
print('YES' if len(a) == len(A) else 'NO')
N = int(input())
A = list(map(int,input().split()))

B = sorted(A)
s = 0
for i in range(0,N-1):
    if B[i] == B[i+1]:
        s = s +1
if s > 0:
    print("NO")
else:
    print("YES")
_ = input()
A = list(map(int,input().split()))
B = set(A)

if len(A) == len(B):
  print('YES')
else:
  print('NO')
N = int(input())
A = list(map(int, input().split()))
A.sort()
a = A[0]
for i in range(1, N):
    if a == A[i]:
        print("NO")
        break
    a = A[i]
else:
    print("YES")
N = int(input()) == len(set(map(int, input().split())))
if N:
  print("YES")
else:
  print("NO")
n = int(input())
nums = list(map(int, input().split()))

print("YES" if len(set(nums)) == len(nums) else "NO")
N = int(input())
A = list(map(int, input().split()))
B = list(set(A))

if len(A) == len(B):
    print('YES')
else:
    print('NO')
N = int(input())
A = list(input().split())

S = set(A)
if len(A) == len(S):
    print('YES')
else:
    print('NO')