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 = int(input())
A = [int(x) for x in input().split()]
A.sort()

ans = 'YES'

for i in range(N-1):
    if A[i] == A[i+1]:
        ans = 'NO'
        break
print(ans)

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

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

Solution (Python):
from collections import Counter
n = int(input())
if(sorted(Counter([i for i in input().split()]).most_common(), key=lambda x: x[1], reverse = True)[0][1] > 1):
  print('NO')
else:
  print('YES')

Solution (Python):



import sys
input = sys.stdin.readline

def main():
    N = int(input())
    A = list(map(int, input().split()))
    A.sort()

    ret = 'YES'
    for i in range(1, N):
        if A[i]==A[i-1]:
            ret = 'NO'
            break
    print(ret)

if __name__ == '__main__':
    main()

Solution (Python):
input();a=list(map(int,input().split()));print("NYOE S"[len(a)==len(set(a))::2])

Solution (Python):
n = int(input())
a = list(map(int, input().split(" ")))
deta = set()
error = False

for i in range(n):
    if n == 0:
        pass
    elif error:
        break
    elif a[i] in deta:
        error = True
        break
    deta.add(a[i])
if error:
    print("NO")
else:
    print("YES")

Solution (Python):
def main():
    N = int(input())
    A = [int(a) for a in input().split()]
    A = sorted(A)
    different = True
    for i in range(N-1):
        if A[i] == A[i+1]:
            different = False
    if different:
        print("YES")
    else:
        print("NO")
if __name__ == "__main__":
    main()

Solution (Python):
def main():
    N = int(input())
    print("NO" if len(set(map(lambda x: int(x), input().split(" ")))) != N else "YES")

main()

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

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

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)
print("YES" if len(B)==N else "NO")

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

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

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

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

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

Solution (Python):
def main():
    input()
    nums = list(map(int, input().split()))
    nums_count = {}

    for i in range(len(nums)):
        nums_count.setdefault(nums[i], 0)
        nums_count[nums[i]] += 1
        if nums_count[nums[i]] >= 2:
            print('NO')
            exit()
    print('YES')




if __name__ == '__main__':
    main()

Solution (Python):
num=int(input())
num_set={int(i) for i in input().split()}
if num==len(num_set):
  print("YES")
else:
  print("NO")

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

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

Solution (Python):
stdin = open(0).read().split('\n')
N = int(stdin[0])
A = list(map(int,stdin[1].split()))
B = set(A)
print('YES' if len(A)==len(B) else 'NO')

Solution (Python):
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')

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

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

s = set(A_list)

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

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

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

c = 0

b = sorted(a) 

for i in range(n-1):
	if b[i] == b[i+1]:
		c += 1

if c >= 1:
	print('NO')
else:
	print('YES')

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

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

S=set(L)

if n==len(S):
	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())
num = list(map(int,input().split()))

num.sort()

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

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

Solution (Python):
N = int(input())
l = [int(x) for x in input().split()]
from collections import defaultdict
d = defaultdict(int)
for i in range(N):
    if d[l[i]] == 1:
        print("NO")
        exit()
    d[l[i]]= 1
print("YES")

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

Solution (Python):
n=int(input())
s=list(map(int,input().split()))
print('YES' if len(set(s))==n else '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(map(int, input().split()))
a_2 = set(a)
if len(a) == len(a_2):
    print("YES")
else:
    print("NO")

Solution (Python):

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

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

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

Solution (Python):
from collections import Counter
n = int(input())
n_list = list(map(int,input().split()))
counter_n_list = Counter(n_list)

n_list_mostcommon = counter_n_list.most_common()
if n_list_mostcommon[0][1] != 1:
    print("NO")
else:
    print("YES")

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

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())
print('YES' if len(set(input().split())) == N else 'NO')

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

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

Solution (Python):
from collections import deque, Counter as cnt
from collections import defaultdict as dd
from operator import itemgetter as ig
from bisect import bisect_right as bsr
from math import factorial, ceil, floor
import sys
sys.setrecursionlimit(1000000)


args = None
INF = float("inf")
MOD = int(1e9 + 7)


def input(*ps):
    if type(ps[0]) is list:
        return [input(*ps[0][:-1]) for _ in range(ps[0][-1])]
    elif len(ps) == 1:
        return ps[0](next(args))
    else:
        return [p(next(args)) for p in ps]


def nlist(n, v):
    if not n:
        return [] if type(v) is list else v
    return [nlist(n[1:], v) for _ in range(n[0])]


def yesno(v, yes="Yes", no="No", upper=False):
    if upper:
        print([yes.upper(), no.upper()][not v])
    else:
        print([yes, no][not v])


def main():
    """エントリーポイント"""
    N = input(int)
    A = input([int, N])
    yesno(len(A) == len(set(A)), upper=True)


if __name__ == '__main__':
    args = iter(sys.stdin.read().split())
    main()

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

Solution (Python):
N=int(input())
A=list(map(int,input().split()))
list.sort(A)
for i in range(N-1):
    if A[i]-A[i+1]==0:
        print("NO")
        exit(0)
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 = [int(i) for i in input().split()]
a = sorted(a)

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()))
b=set()
for i in a:
  b.add(i)
if len(a)==len(b):
  print('YES')
else:
  print('NO')

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

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

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

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

pond = set()
for num in data:
    if not num in pond:
        pond.add(num)
    else:
        print('NO')
        exit()
print('YES')

Solution (Python):
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')

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

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

Solution (Python):
import math

n = int(input())
aL = list(map(int, input().split(" ")))

s = set()
for a in aL:
    if a in s:
        print("NO")
        exit()
    else:
        s.add(a)

print("YES")

Solution (Python):
def main():
    n = int(input())
    a = list(map(int, input().split()))
    mm = {0:0}

    ans = 'YES'
    for i in range(n):
        if mm.get(a[i]) != None:
            ans = 'NO'
            break
        else:
            mm[a[i]] = 1
    
    print(ans)

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=int(input())
s=list(map(int,input().split()))
s.sort()

cnt=0
for i in range(n-1):
    if s[i]==s[i+1]:
        print('NO')
        exit()
    else:
        cnt+=1
if cnt==n-1:            
    print('YES')

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

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

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

Solution (Python):
import sys

n, *a = map(int, sys.stdin.read().split())

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

if __name__ ==  '__main__':
    main()

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

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

Solution (Python):
N = int(input())
A = [int(x) for x in input().split()]
la = len(A)
B = set(A)
lb = len(B)
if la == lb:
  print("YES")
else:
  print("NO")

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

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

Solution (Python):
def judge(s):
  s=sorted(s)
  ls=len(s)
  t=list(set(s))
  lt=len(t)
  if ls==lt:
    return "YES"
  else:
    return "NO"

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

Solution (Python):
n = int(input())
a = [int(i) for i in input().split()]
dic = {}
for i in range(n):
	try:
		dic[a[i]] += 1
	except:
		dic[a[i]] = 1
if max(dic.values()) > 1:
	print("NO")
else:
  	print("YES")

Solution (Python):










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

def calculate(n,arr):

    dict = {}
    result = True
    for i in range(n):
        item = arr[i]
        if dict.get(item) == None:
            dict.__setitem__(item,True)
        else:
            result = False
            break
    if result == True:
        print("YES")
    else:
        print("NO")

calculate(N,ARR)

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

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

A_ = list(set(A));

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

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

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

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

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

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

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

Solution (Python):
import sys
input = sys.stdin.readline
rs = lambda: input().strip()
ri = lambda: int(input())
rl = lambda: list(map(int, input().split()))
mod = 10**9 + 7

N = ri()
A = rl()

h = {}
for a in A:
	if a in h:
		print('NO')
		exit()
	h[a] = 1
print('YES')

Solution (Python):
import sys
input = sys.stdin.readline

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

Solution (Python):










mod = 10**9 + 7

def readInts():
  return list(map(int,input().split()))
def main():
    n = int(input())
    A = sorted(readInts())
    dic = {}
    for a in A:
        if a in dic:
            print('NO')
            exit()
        else:
            dic[a] = 1
    print('YES')
if __name__ == '__main__':
  main()

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

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

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

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

Solution (Python):
s=input()
t=list(map(int,input().split()))
u=len(t)
v=len(set(t))

if u == v:
  print("YES")
else:
  print("NO")

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

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

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

Solution (Python):
from  collections import Counter
n = int(input())
a = Counter([int(x) for x in input().split()])
print('NO') if len(a)!=n else print('YES')

Solution (Python):
from  collections import Counter
n = int(input())
a = Counter([int(x) for x in input().split()])
print('NO') if len(a)!=n else print('YES')

Solution (Python):
from  collections import Counter
n = int(input())
a = Counter([int(x) for x in input().split()])
print('NO') if a.most_common()[0][1]>1 else print('YES')

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

Solution (Python):
'''
INPUT SHORTCUTS
N, K = map(int,input().split())
N ,A,B = map(int,input().split())
string = str(input())
arr = list(map(int,input().split()))
N = int(input())
'''

N = int(input())
arr = list(map(int,input().split()))
arr.sort()
ans = 0
for i in range(N-1):
	if arr[i]==arr[i+1]:
		ans = 1
		break

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

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

dict1 = {}
for i in range(n):
  if dict1.get(an[i], -1) == -1:
    dict1[an[i]] = 1
  else:
    dict1[an[i]] += 1
    
for a, b in dict1.items():
  if b != 1:
    print('NO')
    exit()
    
print('YES')

Solution (Python):
N=int(input())
A=set(map(int,input().split()))
print('YNEOS'[N!=len(A)::2])

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

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

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

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

Solution (Python):
from collections import defaultdict

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

d = defaultdict(int)

for i in range(n):
    if a[i] in d.keys():
        d[a[i]] += 1
    else:
        d[a[i]] = 1

if max(d.values()) >= 2:
    print("NO")
else:
    print("YES")

Solution (Python):
import sys
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")
        sys.exit()

print("YES")

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

Solution (Python):
n=int(input())
a=list(map(int,input().split()))
ans=0
b=sorted(a)
for i in range(n-1):
  if b[i]==b[i+1]:
    ans=1
    break
if ans==1:
  print('NO')
else:
  print('YES')

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

if len(a)==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):
from math import floor,ceil,sqrt,factorial,log
from collections import Counter, deque
from functools import reduce
import numpy as np
def S(): return input()
def I(): return int(input())
def MS(): return map(str,input().split())
def MI(): return map(int,input().split())
def FLI(): return [int(i) for i in input().split()]
def LS(): return list(MS())
def LI(): return list(MI())
def LLS(): return [list(map(str, l.split() )) for l in input()]
def LLI(): return [list(map(int, l.split() )) for l in input()]
def LLSN(n: int): return [LS() for _ in range(n)]
def LLIN(n: int): return [LI() for _ in range(n)]

n = I()

A = FLI()

flg = len(set(A)) == n

print("YES" if flg else "NO")

Solution (Python):
n = int(input())
a = set(list(map(int, input().split())))
print('YES' if len(a)==n else '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=sorted(a)
p=0
for i in range(N-1):
	if a[i]==a[i+1]:
		p=1
if p==0:
	print('YES')
else:
	print('NO')

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

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

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

Solution (Python):

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

Solution (Python):
import numpy as np
def f(n, a):
    if len(np.unique(a)) == n:
        print('YES')
    else:
        print('NO')

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

f(n, a)

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

B =list(set(A))

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

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

x = 0

for i in range(n-1):
    if a[i] == a[i+1]:
        x += 1
        break
    else:
        x += 0
        
if x == 0:
    print('YES')
else:
    print('NO')

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

l.sort()

print('YES' if all([l[i]!=l[i+1] for i in range(n-1)]) else 'NO')

Solution (Python):
import sys, 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, groupby
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(int, input().split()))
def ZIP(n): return zip(*(MAP() for _ in range(n)))
sys.setrecursionlimit(10 ** 9)
INF = float('inf')
mod = 10 ** 9 + 7

N = INT()
A = LIST()

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

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

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

Solution (Python):
N = int(input())
A = list(map(int, input().split()))
A.sort()
flag = 1
for i in range(N-1):
  if(A[i] == A[i+1]):
    flag = 0
    break
    
if(flag == 1):
  print('YES')
else:
  print('NO')

Solution (Python):
N = int(input())
A = list(map(int, input().split()))
A.sort()
flag = 1
for i in range(N-1):
  if(A[i] == A[i+1]):
    flag = 0
    break
    
if(flag == 1):
  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(map(int, input().split()))

s = {}
flag = 0

for i in range(n):
    t = a[i]
    s.setdefault(t, 0)
    if s[t] == 0:
        s[t] = 1
    else:
        print("NO")
        flag = 1
        break

if flag == 0:
    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 =list(map(int ,input().split()))
s =set(A)
if len(A) >len(s):
    print('NO')
else:
    print('YES')

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

Solution (Python):
import sys
def input(): return sys.stdin.readline().rstrip()
def main():
    n=int(input())
    A=[int(_) for _ in input().split()]
    if len(set(A))==n:print("YES")
    else:print("NO")

if __name__=='__main__':
    main()

Solution (Python):
import sys
def input(): return sys.stdin.readline().rstrip()
def main():
    n=int(input())
    A=[int(_) for _ in input().split()]
    if len(set(A))==n:print("YES")
    else:print("NO")

if __name__=='__main__':
    main()

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

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

Solution (Python):
n=int(input())
a=list(map(int,input().split()))
l=len(a)
m=len(set(a))

print("YES" if l==m else "NO")

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

Solution (Python):




if True:
    N=int(input())
    A=[int(i) for i in input().split()]
    print('YES' if len(A)==len(set(A)) else 'NO')

Solution (Python):
N=int(input())
A=[int(item) for item in input().split()]
S=set()
for i in range(N):
    if A[i] in S:
        print("NO")
        exit()
    else:
        S.add(A[i])

print("YES")

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

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

Solution (Python):
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
sys.setrecursionlimit(10 ** 7)

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

Solution (Python):
n =int(input())
a = list(map(int, input().split()))
print('YES' if len(list(set(a))) == n 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):

import sys

sr = lambda: sys.stdin.readline().rstrip()
ir = lambda: int(sr())
lr = lambda: list(map(int, sr().split()))

N = ir()
A = lr()
bl = len(set(A)) == N
print('YES' if bl else 'NO')

Solution (Python):
"""
int(input())
map(int,input().split())
list(map(int,input().split()))

"""

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

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

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

a.sort()

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

Solution (Python):
import os

def main():
	num = int(input())
	list_num = set(map(int, input().split()))
	if len(list_num) != num:
		print("NO")
	else:
		print("YES")

if __name__ == "__main__":
	main()

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

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

Solution (Python):
import collections
N = int(input())
A = list(map(int, input().split()))
c = collections.Counter(A)
values,counts = zip(*c.most_common())
if counts[0] != 1:
    print('NO')
else :
    print('YES')

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

Solution (Python):
n = int(input())
list = []
a = input().split()
for i in range(0, len(a)):
    list.append(int(a[i]))
if len(list)==len(set(list)):
    print('YES')
else:
    print('NO')

Solution (Python):
import sys
N = int(input())
An = sorted(list(map(int,input().split())))

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

Solution (Python):


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



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

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

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

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

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

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

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

s = collections.Counter(A)
if len(s.keys()) == N:
    print('YES')
else:
    print('NO')

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

if N==len(An):
    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):
n = int(input())
a = [int(v) for v in input().split()]
a.sort()

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

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


if __name__ == "__main__":
    main()

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=sorted(list(input().split()))
flag=1
for i in range(N-1):
  if A[i]==A[i+1]:
    flag=0
    break
if flag==1:
  print('YES')
else:
  print('NO')

Solution (Python):
n = int(input())
a = list(map(int, input().split()))
a_dic = {}
flag = 0
for i in range(n):
    if not a[i] in a_dic:
        a_dic[a[i]] = 0
    else:
        flag = 1
print("YES" if flag == 0 else "NO")

Solution (Python):
import numpy as np

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

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

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

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

print(answer)

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

a_list = [int(s) for s in input().split()]
a_set = set(a_list)

ans = "YES" if len(a_list) == len(a_set) else "NO"
print(ans)

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()))
ans = collections.Counter(A)
pr = 'YES'
for i in ans.values():
    if i > 1:
        pr = 'NO'
print(pr)

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

Solution (Python):
import sys
input = sys.stdin.readline
import numpy as np
def print_ans(N, ar):
    """Test Case
    >>> print_ans(5, [2, 6, 1, 4, 5])
    YES
    >>> print_ans(6, [4, 1, 3, 1, 6, 2])
    NO
    >>> print_ans(2, [10000000, 10000000])
    NO
    """
    br = set(ar)
    print("YES" if len(br) == N else "NO")
    

if __name__ == '__main__':
    N = int(input().rstrip())
    ar = list(map(int,input().rstrip().split()))
    print_ans(N, ar)

Solution (Python):
n = int(input())
num = list(map(int, input().split()))
dic = {}

for i in range(n):
  if num[i] not in dic:
    dic[num[i]] = 1
  else:
    print('NO')
    exit()

print('YES')