Problem:
 Score : 300 points    Problem Statement Given is a sequence of integers A_1, A_2, ..., A_N .
If its elements are pairwise distinct, print YES ; otherwise, print NO .      Constraints  2 ≤ N ≤ 200000  1 ≤ A_i ≤ 10^9  All values in input are integers.         Input Input is given from Standard Input in the following format:  N  A_1  ...  A_N       Output If the elements of the sequence are pairwise distinct, print YES ; otherwise, print NO .        Sample Input 1 5
2 6 1 4 5      Sample Output 1 YES  The elements are pairwise distinct.       Sample Input 2 6
4 1 3 1 6 2      Sample Output 2 NO  The second and fourth elements are identical.       Sample Input 3 2
10000000 10000000      Sample Output 3 NO

Solution (Python):
n = input()
arr = map(int,raw_input().strip().split())
new = set(arr)
if len(new)==len(arr):
    print ("YES")
else:
    print("NO")

Solution (Python):
N = input()
arr = input().split()

new_arr = set(arr)

if(len(arr) == len(new_arr)):
    print("YES")
else:
    print("NO")

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

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

Solution (Python):
def main(n, a):
    if len(set(a)) == n:
        print("YES")
    else:
        print("NO")


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

    main(n, a)

Solution (Python):
N = int(input())
As = [int(i) for i in input().split()]

d = {}
for a in As:
    if a not in d:
        d[a] = 0

if len(As) == len(d):
    print('YES')
else:
    print('NO')

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

A = sorted(A)

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

if flag == 0:
    print("YES")
else:
    print("NO")

Solution (Python):








import collections

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

if c.most_common()[0][1] == 1:
    print('YES')
else:
    print('NO')

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

l = len(set(A))

if N == l :
    print("YES")
else:
    print("NO")

Solution (Python):
from sys import stdin

if __name__ == '__main__':
    N = int(stdin.readline().rstrip())
    A = stdin.readline().rstrip().split()
    ori_len = len(A)
    setA = set(A)
    set_len = len(setA)
    if ori_len == set_len:
        print('YES')
    else:
        print('NO')

Solution (Python):

import sys






def main():
    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")
            return
    
    print("YES")



    
if __name__ == '__main__':
    main()

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

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

A.sort()
flag=0
for i in range(N-1):
  if A[i]==A[i+1]:
    flag=1
    break
if flag==1:
  print("NO")
else:
  print("YES")

Solution (Python):
n = int(input())
a = list(map(int, input().split()))

uni = set(a)

if len(uni) == n:
  print("YES")
else:
  print("NO")

Solution (Python):
def main():
    n = int(input())
    a = list(map(int, input().split()))
    a.sort()
    ans = 'YES'
    for i in range(len(a)-1):
        if a[i] == a[i+1]:
            ans = 'NO'
            break

    print(ans)


main()

Solution (Python):
N = int(input())
nums = list(map(int, input().split()))
s = set()
for num in nums:
    if num in s:
        print('NO')
        exit()
    s.add(num)
print('YES')

Solution (Python):
from collections import defaultdict

def main():
    memo = defaultdict(int)
    N = int(input())
    nums = list(map(int,input().split()))

    for n in nums:

        if memo[n]:
            return False
        else:
            memo[n] += 1
    return True

if __name__ == '__main__':
    if main():
        print("YES")
    else:
        print("NO")

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

A.sort()

flag=0

for i in range(0,N-1):
    if A[i]==A[i+1]:
        flag=1

if flag==0:
    print('YES')
else:
    print('NO')

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

if len(A) != len(set(A)):
    print("NO")
else:
    print("YES")

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

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

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

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

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

Solution (Python):
N = int(input())
A = [int(x) for x in input().split()]


B = len(set(A))

if N == B:
    print('YES')
else:
    print('NO')

Solution (Python):
N=int(input())

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

a_list.sort()

flag=False
for i in range((N)-1):
    if a_list[i]==a_list[i+1]:
        flag=True
        break

if flag:
    print("NO")
else:
    print("YES")

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

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

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

Solution (Python):
input()
dic = {}
flag=True
for i in input().split():
    if dic.setdefault(i,0)==1:
        flag=False
        break
    dic[i]=1
print("YES" if flag else "NO")

Solution (Python):
n = int(input())
num = list(map(int,input().split()))
num_set = set(num)
if len(num)!=len(num_set):
  print("NO")
else:
  print("YES")

Solution (Python):

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

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

Solution (Python):
n = int(input())
a = list(map(int, input().split()))

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

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

Solution (Python):
print(['YES','NO'][int(input())>len(set(map(int,input().split())))])

Solution (Python):
def main():
  N=int(input())
  A=list(map(int, input().split()))
  A=sorted(A)
  a=A[0]
  for i in range(1,N):
    if a==A[i]:
      print('NO')
      return
    else:
      a=A[i]
  print('YES')
  return

main()

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

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

Solution (Python):
n = input()
arr = [int(_) for _ in input().split()]

if len(arr) == len(set(arr)):
  print("YES")
else:
  print("NO")

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

Solution (Python):
l = int(input())
a = sorted(list(map(int,input().split())))
k = 0
for i in range(0,l-1):
  if(a[i]==a[i+1]):
    k = 1
if(k==1):
  print("NO")
else:
  print("YES")

Solution (Python):





def solv(A):
    A = sorted(A)
    a0 = A[0]
    for a in A[1:]:
        if a0 == a:
            return "NO"
        a0 = a
    return "YES"


if __name__ == "__main__":

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

    ans = solv(A)

    print(ans)

Solution (Python):
def resolve():
    n = int(input())
    a = list(map(int,input().split()))
    sa = set(a)
    if len(a) != len(sa):
        print("NO")
    else:
        print("YES")
resolve()

Solution (Python):

from sys import stdin
from copy import deepcopy
from functools import reduce
from fractions import gcd
import math
import itertools
from collections import Counter
from itertools import chain  
from heapq import heappush, heappop

"""
N = int(input())
A, B = map(int,input().split())
A = list(map(int,input().split())) 
A = [int(input()) for _ in range(N)] 
lst = [list(map(int,input().split())) for i in range(M)] 
"""

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

A = sorted(A)

for i in range(N-1):
  if A[i] == A[i+1]:
    print('NO')
    exit()
else:
  print('YES')

Solution (Python):
def main():
    n = int(input())
    aa = sorted(list(map(int, input().split())))
    i = 0
    while i < n - 1 and aa[i] != aa[i + 1]:
        i += 1
    if i == n - 1:
        print("YES")
    else:
        print("NO")


if __name__ == "__main__":
    main()

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

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

exists = set()

for a in A:
    if a in exists:
        print('NO')
        break
    exists.add(a)
else:
    print('YES')

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

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

Solution (Python):
I = int(input())
A = set(map(int, input().split()))
if I == len(A):
    print("YES")
else:
    print("NO")

Solution (Python):
N = int(input())
As = list(map(int,input().split()))

As.sort()

for i in range(N-1):
    if As[i] == As[i+1]:
        print("NO")
        exit()
print("YES")

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

Solution (Python):
n = int(input())
A = [int(i) for i in input().split()]

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

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

aSet = set(A)

if len(aSet) < len(A):
    print('NO')
else:
    print('YES')

Solution (Python):
from collections import Counter


len_arr = int(input())
arr = list(map(int, input().split()))
c = Counter(arr)

m = c.most_common(1)[0][1]

if m == 1:
    print("YES")
else:
    print("NO")

Solution (Python):
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()

Solution (Python):







import math
import string

def intinput():
    return int(input())

def listintinput():
    return list(map(int,input().split()))

def splitintinput():
    return map(int,input().split())

N = intinput()
dic = {}
A = listintinput()
flag = 0
for i in A:
    if i in dic:
        flag = 1
        break
    else:
        dic[i] = 1

if flag == 0:
    print('YES')
else:
    print('NO')

Solution (Python):
N = int(input())

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

a_set = set(A)

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

Solution (Python):


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

lastA = None
for a in A:
    if a == lastA:
        print('NO')
        break
    
    lastA = a
else:
    print('YES')

Solution (Python):
n = int(input())
a = input().split(" ")
b = set(a)
if len(b)<len(a):
    answer = "NO"
else:
    answer = "YES"
print(answer)

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

Solution (Python):
n=int(input())
num=[int(i) for i in input().split()]

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

Solution (Python):
n = int(input())
a = list(map(int,input().split()))

b = set(a)

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

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

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

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

Solution (Python):

si = lambda: input()
ni = lambda: int(input())
nm = lambda: map(int, input().split())
nl = lambda: list(map(int, input().split()))
n=int(input())
a=nl()
d=set(a)

if len(d)==n:
    print('YES')
elif len(d)<n:
    print('NO')

Solution (Python):
import sys
from collections import deque, Counter, defaultdict
from fractions import gcd
input = sys.stdin.readline

def eprint(s):
    if type(s) != type('str'):
        s=str(s)

    sys.stderr.write(s+'\n')
    return

def main():
    n = int(input())
    As = list(map(int, input().split()))
    As.sort()
    for i in range(n-1):
        if As[i+1] == As[i]:
            print('NO')
            return
    print('YES')
    return

if __name__ == '__main__':
    main()

Solution (Python):
n=int(input())
l1=list(map(int,input().split()))
l2=list(set(l1))
L2=len(l2)
print('YES' if n==L2 else 'NO')

Solution (Python):
N = int(input())
A = list(map(int, input().split()))
s = set(A)
result = "YES" if len(s) == len(A) else "NO"
print(result)

Solution (Python):
def main():
    n = int(input())
    data = set()
    for i in input().split(" "):
        if i in data:
            print("NO")
            return
        data.add(i)
    print("YES")


if __name__ == '__main__':
    main()

Solution (Python):

N = int(input())

array = map(int, input().split())

if N == len(set(array)):
    print('YES')
else:
    print('NO')

Solution (Python):
import unittest


class TestC(unittest.TestCase):
    def test_1(self):
        self.assertEqual(think([2, 6, 1, 4, 5]), 'YES')

    def test_2(self):
        self.assertEqual(think([4, 1, 3, 1, 6, 2]), 'NO')

    def test_3(self):
        self.assertEqual(think([10000000, 10000000]), 'NO')


def solve():
    a = read()
    result = think(a)
    write(result)


def read():
    n = read_int(1)[0]
    return read_int(n)


def read_int(n):
    return read_type(int, n, sep=' ')


def read_float(n):
    return read_type(float, n, sep=' ')


def read_type(t, n, sep):
    return list(map(lambda x: t(x), read_line().split(sep)))[:n]


def read_line(n=0):
    if n == 0:
        return input().rstrip()
    else:
        return input().rstrip()[:n]


def think(a):
    return 'YES' if len(a) == len(set(a)) else 'NO'


def write(result):
    print(result)


if __name__ == '__main__':
    
    solve()

Solution (Python):
import sys
import math
def i():return int(sys.stdin.readline().replace("\n",""))
def i2():return map(int,sys.stdin.readline().replace("\n","").split())
def s():return str(sys.stdin.readline().replace("\n",""))
def l():return list(sys.stdin.readline().replace("\n",""))
def intl():return [int(k) for k in sys.stdin.readline().replace("\n","").split()]
def lx():return list(map(lambda x:int(x)*-1,sys.stdin.readline().replace("\n","").split()))
def t():return tuple(map(int,sys.stdin.readline().replace("\n","").split()))

if __name__ == "__main__":pass
n = i()
a = intl()
a = list(set(a))
if len(a) == n:
    print("YES")
else:
    print("NO")

Solution (Python):
n = int(input())
a = list(map(int, input().split()))

d = dict()
for i in a:
    d[i] = d.get(i, 0) + 1

for n in d.values():
    if n != 1:
        print("NO")
        exit()
print("YES")

Solution (Python):
N=int(input())
S=list(map(int,input().split()))
P=set(S)
Q=len(P)
if N==Q:
	print("YES")
else:
	print("NO")

Solution (Python):
N = int(input())
L = list(map(int,input().split()))
M = set(L)
if len(L) == len(M):
    print('YES')
else:
    print('NO')

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

Solution (Python):
N = int(input())
print("YES" if N == len(set(input().split())) else "NO")

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

Solution (Python):
n = int(input())
a = [int(i) for i in input().split()]
set_a = set(a)
if len(set_a) == len(a):
    print('YES')
else:
    print('NO')

Solution (Python):
N = int(input())
A = list(map(int, input().split())) 
B = set(A)

if len(A) == len(B):
  print("YES")
else:
  print("NO")

Solution (Python):
n = int(input())
a_list = sorted(list(map(int, input().split())))

for i in range(len(a_list) - 1):
    if a_list[i] == a_list[i+1]:
        print("NO")
        break
else:
    print("YES")

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

Solution (Python):
N = int(input())
As = list(map(str, input().split()))

lis = dict()

for A in As:
  if A in lis:
    print("NO")
    exit()
  else:
    lis[A] = 0
print("YES")

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

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

Solution (Python):
n = int(input())
a = [int(i) for i in input().split()]
def has_duplicates(seq):
    return len(seq) != len(set(seq))

if has_duplicates(a):
    print('NO')
else:
    print('YES')

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

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

Solution (Python):
n = int(input())
a = [i for i in input().split()]

a.sort()
for i in range(n-1):
    if a[i] == a[i+1]:
        print('NO')
        exit()
print('YES')

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

Solution (Python):
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")

Solution (Python):
import numpy as np

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

if len(a) == len(np.unique(a)):
    print('YES')
else:
    print('NO')

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

Solution (Python):


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

Solution (Python):


n = int(input())
a = list(map(int, input().split()))
check_dict = {}
flag = 0
for i in range(n):
    if a[i] in check_dict:
        flag = 1
        break
    else:
        check_dict[a[i]] = 1

if flag == 1:
    print("NO")
else:
    print("YES")

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

a = set(A)

if len(A) == len(a):
    print("YES")
else:
    print("NO")

Solution (Python):
n = int(input())
a = set([ int(v) for v in input().split() ])

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

Solution (Python):
print('YES' if int(input())==len(set(input().split())) else 'NO')

Solution (Python):


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

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

print('YES' if ans else 'NO')

Solution (Python):
n = int(input())
a = list(map(int,input().split()))
a = sorted(a)
f = True

for i,j in enumerate(a[:-1]):
    if(a[i] == a[i+1] ):
        f = False
        break
if f:
    print("YES")
else:
    print("NO")

Solution (Python):
def solve():
  N = int(input())
  A = list(map(int, input().split()))
  ret = len(set(A)) == N
  print('YES' if ret else 'NO')
  
solve()

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

Solution (Python):
n = int(input())
a = list(map(int , input().split()))
d = {}
for ai in a:
    if ai in d:
        print('NO')
        exit()
    else:
        d[ai] = 1
print('YES')

Solution (Python):
n=int(input())
a=list(map(int,input().split()))

new=sorted(a)

for i in range(n-1):
    if new[i]==new[i+1]:
        print("NO")
        break
    if i==n-2 and new[i]!=new[i+1]:
        print("YES")

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

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

Solution (Python):
import collections
n = int(input())
a = list(map(int,input().split()))

c = collections.Counter(a)
if (c.most_common()[0][1]) == 1:
    print("YES")
else:
    print("NO")

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

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

Solution (Python):

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

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

Solution (Python):

N = int(input())
A = list(map(int, input().split()))
A_1 = list(set(A))
if len(A) == len(A_1):
    print("YES")
else:
    print("NO")

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

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

Solution (Python):
from collections import Counter

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

cnt = Counter(A)

for i in cnt:
    if cnt[i] > 1:
        print("NO")
        exit()

print("YES")

Solution (Python):

def solve(N, A):
    for i in range(N-1):
        if A[i] == A[i+1]:
            return "NO"
    return "YES"
N = int(input())
A = sorted([int(x) for x in input().split()])
print(solve(N, A))

Solution (Python):
N = int(input())
An = [int(n) for n in input().split()]
Nset = len(set(An))
print("YES" if N == Nset else "NO")

Solution (Python):
inputf = input

N = inputf()
A = [int(x) for x in inputf().split(' ')]
A_ = set(A)

if len(A) == len(A_):
    print("YES")
else:
    print("NO")

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

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

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

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

Solution (Python):
import numpy as np

N=int(input())

A=np.array(input().split(" "),dtype=np.int32)

tA=list(set(A))

if(len(A)==len(tA)):
    print("YES")
else:
    print("NO")

Solution (Python):
N = int(input())
a_list = list(map(int, input().split(" ")))
if len(set(a_list)) < N:
    print("NO")
else:
    print("YES")

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

Solution (Python):
N = int(input())
An = list(map(int,input().split(' ')))
D = {}
for a in An:
    if a in D:
        print('NO')
        exit(0)
    else:
        D[a] = 1
print('YES')

Solution (Python):
import sys
import re
from collections import deque, defaultdict, Counter
from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
from itertools import accumulate, permutations, combinations, product
from operator import itemgetter, mul
from copy import deepcopy
from string import ascii_lowercase, ascii_uppercase, digits
from bisect import bisect, bisect_left
from fractions import gcd
from heapq import heappush, heappop
from functools import reduce
def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(): return list(map(str, input().split()))
sys.setrecursionlimit(10 ** 9)
INF = float('inf')
mod = 10 ** 9 + 7


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


N = INT()
A = LIST()

if has_duplicates(A):
    print('NO')
else:
    print('YES')

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

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

Solution (Python):
import queue
import copy
import math
from collections import deque
import bisect


n = int(input())


an = input().split()

s_an = set(an)

if len(an) == len(s_an):
    print("YES")
else:
    print("NO")

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

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

A.sort()

s = 0
ans = "YES"
for i in A:
    if i > s:
        s = i
    else:
        ans = "NO"
        break
print(ans)

Solution (Python):
n = input()
an = list(map(int, input().split()))

newn = set(an)

if len(newn) == len(an):
    print('YES')
else:
    print('NO')

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

Solution (Python):
N = int(input())
L=list(map(int,input().split()))
L=sorted(L)

for i in range(N-1):
    if(L[i]==L[i+1]):
        print("NO")
        exit()

print("YES")

Solution (Python):
n = int(input())
a = sorted(list(map(int, input().split())))

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

if flag:
    print("YES")
else:
    print("NO")

Solution (Python):
def solve():
    N = int(input())
    A = list(map(int, input().split()))

    sortedA = sorted(A)
    prev = sortedA[0]
    for i in range(1, N):
        if sortedA[i] == prev:
            print('NO')
            break
        
        prev = sortedA[i]
    else:
        print('YES')


if __name__ == '__main__':
    solve()

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

from collections import defaultdict
cnt=defaultdict(int)
for i in range(N):
  cnt[A[i]]+=1
  
keys=cnt.keys()
out='YES'
for i in keys:
  if cnt[i]>1:
    out='NO'
    
print(out)

Solution (Python):
import math
import numpy as np
from fractions import gcd
import fractions
import statistics
import collections
from functools import reduce
import itertools
from collections import defaultdict
import bisect
from fractions import Fraction
 

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

c = collections.Counter(A)

for k,v in c.items():
    if v >=2:
        print('NO')
        exit()

print('YES')

Solution (Python):
n = int(input())
A = map(int, input().split())

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

Solution (Python):
n = int(input())
a = list(map(int, input().split()))
d = {}
ans = "YES"
for i in a:
  if i in d:
    ans = "NO"
  d[i] = 1
print(ans)

Solution (Python):
N = int(input())
A = [int(i) for i in input().split()]
from collections import defaultdict as ddict
ans = ddict(int)
result = True
for a in A:
    ans[a] += 1
    if ans[a] > 1:
        result = False
        break
print("YES") if result else print("NO")

Solution (Python):
N = int(input())
A = sorted(map(int,input().split()))

for i in range(len(A)-1):
    if A[i]==A[i+1]:
        print('NO')
        exit()

print('YES')

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

Solution (Python):
from collections import defaultdict
N=int(input())
Alist=input().split()
Adict=defaultdict(int)
for A in Alist:
    Adict[A]+=1
    if Adict[A]==2:
        print("NO")
        break
else:
    print("YES")

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

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

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

Solution (Python):
from collections import Counter

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

C = Counter(A)
for i in C.values():
    if i != 1:
        print("NO")
        exit()
print("YES")

Solution (Python):
from collections import Counter

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

c = Counter(A)

for count in c.values():
    if count != 1:
        print("NO")
        exit()

print("YES")

Solution (Python):




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

a.sort()


ans = "YES"
for i in range(1, n):
    if a[i-1] == a[i]:
        ans = "NO"
        break


print(ans)

Solution (Python):
n=int(input())
a=list(map(int,input().split()))
d=dict()
for i in range(n):
  if a[i] not in d:
    d[a[i]]=0
  else:
    print('NO')
    exit()
print('YES')

Solution (Python):
def run():
  N = int(input())
  NA = len(set(map(int, input().split())))
  if N == NA:
    print('YES')
  else:
    print('NO')

if __name__ == '__main__':
    run()

Solution (Python):
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)

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

As = sorted(A)

for i in range(N-1):
    if As[i] == As[i+1]:
        break
else:
    print('YES')
    exit()
print('NO')

Solution (Python):
a = int(input())
n = list(map(int, input().split()))
p2 = len(n)
p1 = len(list(set(n)))
if(p1 == p2):print("YES")
else:print("NO")

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

Solution (Python):
import collections
n=int(input())
a=list(map(int,input().split()))
if n==len(collections.Counter(a)):
    print("YES")
else:
    print("NO")

Solution (Python):
from collections import Counter
N = int(input())
a_dict = Counter(map(int,input().split()))

if a_dict.most_common()[0][1]>1:
    ans = "NO"
else:
    ans = "YES"
print(ans)

Solution (Python):
N = int(input())
arr = list(map(int,input().split()))

if len(arr) == len(set(arr)):
  print("YES")
else:
  print("NO")

Solution (Python):
N = int(input())
A = list(map(int, input().split()))
d = {}
for i in A:
    d.setdefault(i)
if len(d) == len(A):
    print("YES")
else:
    print("NO")

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

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

Solution (Python):
def main(n,a):
    a.sort()
    for i in range(1,len(a)):
        if a[i] == a[i-1]:
            return "NO"
    return "YES"

n = int(input())
a = list(map(int,input().split()))
print(main(n,a))

Solution (Python):
N = input()
A = input().split(" ")
N = int(N)
set_A = set(A)
if len(set_A) == N:
    print("YES")
else:  
    print("NO")

Solution (Python):
import sys
 
N = int(input())
A = list(map(int, input().split()))
 
A.sort()
 
before = 0
for i in range(N):
    if A[i] == before:
        print("NO")
        sys.exit()
    before = A[i]
 
print("YES")

Solution (Python):
N = int(input())
L = list(map(int, input().split()))
if len(set(L)) == len(L):
    print("YES")
else:
    print("NO")

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

if __name__ == "__main__":
    resolve()

Solution (Python):

import sys

YES = "YES"  
NO = "NO"  


def solve(N: int, A: "List[int]"):
    print(YES if len(A)==len(set(A)) else NO)
    return



def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  
    A = [int(next(tokens)) for _ in range(N)]  
    solve(N, A)

if __name__ == '__main__':
    main()

Solution (Python):
n = int(input())
def has_duplicates(seq):
    return len(seq) != len(set(seq))
if has_duplicates(list(map(int,input().split()))):
    print("NO")
else:
    print("YES")

Solution (Python):
import sys
from collections import Counter

N=input()
A=map(int, sys.stdin.readline().split())

C=Counter(A)
if len(C)==N:
    print "YES"
else:
    print "NO"

Solution (Python):
import collections
n=int(input())
a=list(map(int, input().split()))

a=collections.Counter(a)
a=list(a.most_common())

if a[0][1]==1:
    print('YES')
else:
    print('NO')