Problem:
 Score: 200 points    Problem Statement  Takahashi bought a piece of apple pie at ABC Confiserie. According to his memory, he paid N yen (the currency of Japan) for it.  The consumption tax rate for foods in this shop is 8 percent. That is, to buy an apple pie priced at X yen before tax, you have to pay X \times 1.08 yen (rounded down to the nearest integer).  Takahashi forgot the price of his apple pie before tax, X , and wants to know it again. Write a program that takes N as input and finds X . We assume X is an integer.  If there are multiple possible values for X , find any one of them. Also, Takahashi's memory of N , the amount he paid, may be incorrect. If no value could be X , report that fact.      Constraints   1 \leq N \leq 50000  N is an integer.         Input  Input is given from Standard Input in the following format:  N       Output  If there are values that could be X , the price of the apple pie before tax, print any one of them. If there are multiple such values, printing any one of them will be accepted. If no value could be X , print :( .        Sample Input 1 432      Sample Output 1 400  If the apple pie is priced at 400 yen before tax, you have to pay 400 \times 1.08 = 432 yen to buy one. Otherwise, the amount you have to pay will not be 432 yen.       Sample Input 2 1079      Sample Output 2 :(  There is no possible price before tax for which you have to pay 1079 yen with tax.       Sample Input 3 1001      Sample Output 3 927  If the apple pie is priced 927 yen before tax, by rounding down 927 \times 1.08 = 1001.16 , you have to pay 1001 yen.

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

N_notax = int(- (-N // 1.08))

if int(N_notax * 1.08) == N:
    print(N_notax)
else:
    print(":(")

Solution (Python):
import math as ms
N = int(input())

plow = ms.floor(N / 1.08)

flag = 0




if ms.floor(plow * 1.08) == N:
    flag = 1
elif ms.floor((plow + 1) * 1.08) == N:
    flag = 1
    plow += 1
    
if flag == 1:
    print(plow)
else:
    print(":(")

Solution (Python):
import math
def main():
  N = int(input())
  if (N < 1 or N > 50000):
    print(":(")

  estimatedX1 = math.floor(N / 1.08)
  estimatedX2 = math.ceil(N / 1.08)
  
  if (math.floor(estimatedX1 * 1.08) == N):
    print(math.floor(estimatedX1))
  elif (math.floor(estimatedX2 * 1.08) == N):
    print(math.floor(estimatedX2))
  else:
    print(":(")

main()

Solution (Python):
N = int(input())
s = []
for i in range(50000):
    s.append(int((i+1)*1.08))
if N in s:
    print(int(N/1.08+1/1.08))
else:
    print(":(")

Solution (Python):
N=int(input())
X=int(-(-N//1.08))

if int(X*1.08) != N:
    print(":(")
else:
    print(X)

Solution (Python):
import math

n = int(input())

if math.floor(math.floor(n/1.08)*1.08) == n:
    print(math.floor(n/1.08))
elif math.floor((math.floor(n/1.08)+1) *1.08) == n:
    print(math.floor(n/1.08)+1)
else:
    print(':(')

Solution (Python):
import numpy as np
import math
s = input().split(" ")
s = [int(s[i]) for i in range(len(s))]
taxIncludedPrice = s[0]






minPrice = taxIncludedPrice / 1.08
maxPrice = (taxIncludedPrice + 1) / 1.08
fromPrice = math.ceil(minPrice)
toPrice = math.floor(maxPrice)


def getPrice(fromPrice, toPrice):
    for price in range(fromPrice, toPrice + 1):
        if fromPrice >= minPrice and fromPrice < maxPrice:
            return price
        elif toPrice >= minPrice and toPrice < maxPrice:
            return price
    return ":("


print(getPrice(fromPrice, toPrice))

Solution (Python):
import math
N = int(input())
kari = N*100/108
hako = math.ceil(kari)
ans = math.floor(kari)
if  hako*108/100==N or ans*108/100==N:
    print(math.floor(kari))
elif math.floor(hako*108/100)==N:
    print(hako)
elif math.floor(ans*108/100)==N:
    print(ans)

 

 
else:
    print(":(")

Solution (Python):
def kei(x):
    return int(x*1.08)


n=int(input())

kiri=int(n/1.08)

if(kei(kiri)==n):
    print(kiri)
elif(kei(kiri+1)==n):
    print(kiri+1)
else:
    print(":(")

Solution (Python):
import math

n = int(input())
ans = ":("
for i in range(1, n+1):
    v = math.floor(i * 1.08)
    if v == n:
        ans = i
        break

print(ans)

Solution (Python):

import sys
sys.setrecursionlimit(10000000)
INF = 1<<32


def solve(N: int):
    
    for i in range(1, 50000):
        if i*1.08//1 == N:
            print(i)
            exit()
        
    print(':(')



def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  
    solve(N)

if __name__ == '__main__':
    main()

Solution (Python):
import sys
n = int(input())
for i in range(1, n+1):
    if n*100 <= i*108 <(n+1)*100:
        print(i)
        sys.exit()
print(":(")

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


X = N/1.08
if int(X)*1.08==N:
    X=int(N/1.08)
else: 
    X=int(N/1.08) + 1

if X * 1.08 >= N+1:
    print(":(")
else:
    print(X)

Solution (Python):
N = int(input())
for i in range(50000):
    if N == int(i * 1.08):
        ans = i
        break
    else:
        ans = ":("
print(ans)

Solution (Python):
N = float(input())
y = N/1.08 
x = int(y) 
z = float(x) 
flag=y-z
p=1/1.08
if flag==0:
 print(x)
elif flag+p > 1:
 print(x+1)
else:
 print(':(')

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

tax = 1.08
n = N // tax

if math.floor((n) * tax) == N:
    print(int(n))
else:
    while 1:
        if math.floor(n * tax) == N:
            print(int(n))
            break
        elif math.floor(n * tax) < N:
            n += 1
        elif math.floor(n * tax) > N:
            print(":(")
            break

Solution (Python):
import sys
N = int(input())
for i in range(N+1):
    a = int(i * 1.08)
    if N == a:
        print(i)
        sys.exit()
print(':(')

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


x = n / 1.08
x_decimal = x - int(x)

ret = ':('
if x_decimal == 0.0:
    ret = str(int(x))
elif x_decimal > (8 / 108):
    ret = str(int(x + 1))
print(ret)

Solution (Python):

N=int(input())

ans= N / 1.08

if(ans % 1 !=0):
    ans= (ans //1)+1




if((ans * 1.08)//1 == N):
    print(int(ans))
else:
    print(":(")

Solution (Python):
n = int(input())
left = n / 1.08 
right = (n+1) / 1.08
if right == int(right):
    right = int(right) - 1
else:
    right = int(right)

if left == int(left):
    left = int(left)
else:
    left = int(left) + 1

if left <= right:
    print(left)
else:
    print(":(")

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

ans = 0

for i in range(100):
    val = 100 * n + i
    if val % 108 == 0:
        ans = val // 108
        break
    else:
        pass

print(':(') if ans == 0 else print(ans)

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

N = int(input())
for i in range(50000):
    if math.floor(i * 1.08) == N:
        print(i)
        exit()
print(':(')

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

n1 = int(-(-n // 1.08))
if int(n1* 1.08) == n:
    print(n1)
else:
    print(':(')

Solution (Python):
n = int(input())
x = int(n/1.08)
if int(x*1.08)==n:
    print(x)
else:
    if int((x+1)*1.08)==n:
        print(x+1)
    else:
        print(':(')

Solution (Python):
import math

n = int(input())
x = math.ceil(n/1.08)
y = math.floor(x*1.08)

if n == y:
    print(x)
else:
    print(':(')

Solution (Python):
N=int(input())
X_max=int((N+1)//1.08)
X_min=int(-(-(N//1.08)))

if int(X_max*1.08)==N:
	print(X_max)
elif int(X_min*1.08)==N:
	print(X_min)
else:
	print(':(')

Solution (Python):
N = int(input())
f = True
for i in range(int((N-1)/1.08),int(N/1.08)+2):
    X = int(i*1.08)
    if X == N:
        print(i)
        f = False
        break
if f:
    print(":(")

Solution (Python):
N = int(input())
X = N / 1.08
N_new = int(X) * 1.08
N_new_2 = (int(X) + 1) * 1.08

if X % 1 == 0:
    print(int(X))
elif int(N_new) == N or int(N_new_2) == N:
    print(int(X)+1)
          
else:
    print(":(")

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

no_tax = n / 1.08

no_tax = math.floor(no_tax)

l = [no_tax-1,no_tax,no_tax+1]

for i in l:
    if n == math.floor(i*1.08):
        print(math.floor(i))
        break
else:
    print(":(")

Solution (Python):
import math 
import sys

N = int(input())

n = math.floor(N/1.08)

while n * 1.08 <= N+1:
    
    if math.floor(n*1.08) == N:
        print(n)
        sys.exit()
    else:
        n += 1
print(':(')

Solution (Python):
N = list(map(int, input().split()))[0]

a = float(N) / 1.08



result = ":("
for i in range(3):
    b = int(a) + i
    c = b * 1.08
    d = int(c)
    
    if d == N:
        result = str(b)

print(result)

Solution (Python):
import math
n = int(input())
b=n/1.08

a=math.ceil(b)

if a-b>0.9:
  print(":(")
else:
  print(a)

Solution (Python):
import math
a=int(input())
b=round(a/1.08)
c=math.floor(b*1.08)
d=math.floor((b-1)*1.08)
e=math.floor((b+1)*1.08)

if a==c:
  print(b)
else:
  if a==d:
    print(b-1)
  elif a==e:
    print(b+1)
  else:
  	print(':(')

Solution (Python):
import math

N = int(input())
X = math.ceil(N / 1.08)

if math.floor(X*1.08)==N:
  print(X)
else:
  print(':(')

Solution (Python):
n = int(input())
x = n/1.08
if int(int(x)*1.08) == n:
    print(int(x))
elif int(int(x+1)*1.08) == n:
    print(int(x+1))
else:
    print(':(')

Solution (Python):
n= int(input())
if int(-(-n//1.08)*1.08) == n:
    print(int(-(-n//1.08)))
else:
    print(":(")

Solution (Python):
import math
n = int(input())
a = int(n/1.08)
if math.floor((a+1)*1.08) == n:
  print(a+1)
elif math.floor((a-1)*1.08) == n:
  print(a-1)
elif math.floor(a*1.08) == n:
  print(a)
else:
  print(':(')

Solution (Python):
def is_integer_num(n):
    if isinstance(n, int):
        return True
    if isinstance(n, float):
        return n.is_integer()
    return False
  
N = int(input())
a = N / 1.08
if is_integer_num(a) == True:
  print(int(a))
else:
  a = int(a)
  b = a+1
  
  n = int(a * 1.08)
  m = int(b * 1.08)
  
  if n == N:
    print(a)
  elif m == N:
    print(b)
  else:
    print(":(")

Solution (Python):
import math
import sys

N = int(input())

X = 50000

for i in range(X):
    if math.floor(i*1.08) == N:
        print(i)
        sys.exit()
    else:
        continue
print(":(")

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

X = -1
for i in range(50000):
    if i*108//100 == N:
        X = i
        break

if X == -1:
    print(':(')
else:
    print(X)

Solution (Python):
n = int(input())
lst = []
for i in range(50001) :
    lst += [int(i*1.08)]

if n in lst :
    if int(n/1.08)*1.08 == n :
        print(int(n/1.08))
    else :
        print(int(n/1.08)+1)

else :
    print(":(")

Solution (Python):
import math

N=int(input())

X = N / 1.08
X = math.ceil(X)

N2 = X * 1.08
N2 = math.floor(N2)

if N2 == N:
    print(X)
else:
    print(':(')

Solution (Python):

import math
N = int(input())
tmp = round(N / 1.08)

if math.floor(tmp * 1.08) == N:
    print(int(tmp))
elif math.floor((tmp+1) * 1.08) == N:
    print(int(tmp+1))
else:
    print(":(")

Solution (Python):

N = int(input())

X = N // 1.08
Xminus = X - 1
Xplus = X + 1

X_list = [X, Xplus, Xminus]

flug = False

for x in X_list:

    if int(x * 1.08) == N:
        print(int(x))
        flug = True
        break

if flug == False:
    print(":(")

Solution (Python):
import math
N=int(input())
x=N/1.08
if (math.floor(math.ceil(x)*1.08))!=N:
  print(":(")
else:
  print(math.ceil(x))

Solution (Python):
n = int(input())
import math
for i in range(1, 46298):
    if math.floor(i * 1.08) == n:
        print(i)
        break
else:
    print(":(")

Solution (Python):
from math import floor
n = int(input())
tmp = floor(n / 1.08)
while floor(tmp * 1.08) <= n:
  if floor(tmp * 1.08) == n:
    print(tmp)
    exit()
  else:
    tmp += 1
print(':(')

Solution (Python):
N=int(input())
a=N/1.08
b=(N+1)/1.08
if a//1 == a:
  print(int(a))
elif a//1 ==b//1:
  print(":(")
elif a//1+1 ==b:
  print(":(")
else:
  print(int(a//1+1))

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

x = int(n//1.08)


while True:
    if int(x*1.08) == n:
        ans = x
        break
    
    x += 1
    
    if int(x*1.08) > n:
        ans = ':('
        break
        
print(ans)

Solution (Python):
import math
N = int(input())
X = math.ceil(N / 1.08)
if N == math.floor(1.08 * X):
  print(X)
else:
  print(':(')

Solution (Python):
from math import floor
n = int(input())
val = round(n/1.08)
if floor(val*1.08) == n:
  print(val)
elif floor((val+1)*1.08) ==n:
  print(val+1)
else:
  print(":(")

Solution (Python):
a=int(input())
b=int(a/1.08)
c=int(b*1.08)
if c==a:
    print(b)
else:
    c=int((b+1)*1.08)
    if a==c:
        print(b+1)
    else:
        c=int((b-1)*1.08)
        if a==c:
            print(b-1)
        else:
            print(":(")

Solution (Python):
import math

N=int(input())

X =round(N / 1.08)

if math.floor(X * 1.08) == N:
  print(X)
elif math.floor((X+1) * 1.08) == N:
  print(X+1)
elif math.floor((X-1) * 1.08) == N:
  print(X-1)  
else:
  print(":(")

Solution (Python):
def value(x): return x*108//100
def bsearch(V,x_min,x_max):
    if x_max - x_min == 1: print(":(")
    else:
      x = (x_min + x_max) // 2
      v = value(x)
      if V>v: return bsearch(V,x, x_max)
      elif V<v: return bsearch(V,x_min,x)
      else: print(x)

N = int(input())
bsearch(N, 0,50000)

Solution (Python):
n=int(input())
if n+1>int((n+1)/1.08)*1.08>=n:
  print(int((n+1)/1.08))
else:
  print(':(')

Solution (Python):

N = int(input())

if(N*100 % 108 == 0):
  Xmin = int(N*100/108)
else:
  Xmin = int(N*100/108)+1

if((N+1)*100 % 108 == 0):
  Xmax = int((N+1)*100/108)-1
else:
  Xmax = int((N+1)*100/108)

if(Xmax >= Xmin):
  print(Xmin)
else:
  print(':(')

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

def sol(n):
    for i in range(1,n+1):
        t=i*1.08
        if(int(t)==n):
            return i
    return ":("

print(sol(N))

Solution (Python):
import math

N = int(input())*100

x=N//108

if (math.floor(x*108/100)==N/100):
  print('{:.0f}'.format(x))
elif (math.floor((x+1)*108/100)==N/100):
  print('{:.0f}'.format(x+1))
else:
  print(":(")

Solution (Python):
import math
n=int(input())
ans=math.ceil(n/1.08)
r=math.floor(ans*1.08)
if(n!=r):
  ans=":("
print(ans)

Solution (Python):
import math

n = int(input())

for i in range(1, n + 1):
    if math.floor(i * 1.08) == n:
        print(i)
        break
else:
    print(":(")

Solution (Python):
N = int(input())
x = int(N//1.08)
if int(x*1.08) == N:
  print(x)
elif int((x+1)*1.08) == N:
  print(x+1)
else:
  print(':(')

Solution (Python):



N = int(input())
num1 = int(N / 1.08)
num2 = int(num1 * 1.08)
num3 = int((num1 + 1) * 1.08)
if N == num2:
  print(num1)
elif N == num3:
  print(num1 + 1)
else:
  print(':(')

Solution (Python):


n=int(input())
for i in range(50000):
    if int(i*1.08)==n:
        print(i)
        exit()
else:
    print(':(')

Solution (Python):
import math
n = int(input())
x = math.ceil(n/1.08)
if int(x * 1.08) == n:
  print(x)
else:
  print(":(")

Solution (Python):
from sys import stdin
import math
input = int(stdin.readline().rstrip())

orig = input/1.08

ceil = math.ceil(orig)
floor = math.floor(orig)

if orig == ceil and orig == floor:
    print(int(orig))
elif int(math.floor(ceil) * 1.08) == input:
    print(int(ceil))
elif int(math.floor(floor * 1.08)) == input:
    print(int(floor))
else:
    print(':(')

Solution (Python):
import math
n = int(input())
ok = False
for i in range(n,0,-1):
    if math.floor(i*1.08)==n:
        print(i)
        ok = True
        break
if ok==False:
    print(":(")

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



flag=False
for i in range(N+1):
    if int(i*1.08)==N:
        print(i)
        flag=True
        break

if(flag==False):
    print(":(")

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

a = N/1.08
X = a*10//10

if(int(int(X)*1.08)==N):
  print(int(X))
elif(int((int(X)+1)*1.08)==N):
  print(int(X)+1)
elif(int((int(X)-1)*1.08)==N):
  print(int(X)-1)
else:
  print(":(")

Solution (Python):
n=int(input())
import math
m=math.ceil(n/1.08)
if int(m*1.08)==n:
  print(m)
else:
  print(':(')

Solution (Python):
n = int(input())
flag = False
x = int(n / 108 * 100)
for i in range(x-5,x+5):
    if int(i*1.08) == n:
        flag = True
        x = i
if flag:
    print(x)
else:
    print(":(")

Solution (Python):
N = int(input())
for X in range(0, N + 1):
    if int(X * 1.08) == N:
        print(X)
        break
else:
    print(":(")

Solution (Python):
from math import floor, ceil

n = int(input())
tax = 1.08

x_kari = ceil(n/tax)

n_kari = floor(x_kari*tax)

if n == n_kari:
	print(x_kari)
else:
	print(':(')

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

ans1 = N / 1.08
N2 = int(ans1) * 1.08
ans2 = int(ans1) + 1
N3 = int(ans2) * 1.08

if int(N2) == N:
    print(int(ans1))
elif int(N3) == N:
    print(int(ans2))
else:
    print(":(")

Solution (Python):
import math
n = int(input())
x = math.ceil(n / 1.08)
y = int(x * 1.08)
print(x if n == y else ':(')

Solution (Python):
import math
n1 = int(input())
n =  n1 * 100
x1 = (n // 108)
x2 = -(-n // 108)
if x1*108//100 == n1:
    print(x1)
    exit(0)
if x2*108//100 == n1:
    print(x2)
    exit(0)
print(":(")

Solution (Python):

from decimal import Decimal, ROUND_DOWN, ROUND_UP


def solve(*args: str) -> str:
    n = Decimal(args[0])
    rate = Decimal(1.08)
    x_u = (n/rate).quantize(Decimal('0'), rounding=ROUND_UP)
    x_d = (n/rate).quantize(Decimal('0'), rounding=ROUND_DOWN)

    ret = ''
    if x_u == x_d:
        ret = str(x_u)
    elif (x_u*rate).quantize(Decimal('0'), rounding=ROUND_DOWN) == n:
        ret = str(x_u)
    elif (x_d*rate).quantize(Decimal('0'), rounding=ROUND_DOWN) == n:
        ret = str(x_d)
    else:
        ret = ':('

    return ret


if __name__ == "__main__":
    print(solve(*(open(0).read().splitlines())))

Solution (Python):
import math
n = int(input())
a = math.floor(n / 1.08)
b = a + 1
c = math.floor(a * 1.08)
d = math.floor(b * 1.08)

if c == n:
  print(a)
elif d == n:
  print(b)
else:
  print(":(")

Solution (Python):
N = int(input())
a = N/1.08
b = (N+1)/1.08

inta = int(a)
if inta==a:
    print(inta)
elif inta==int(b) or (int(b)==b and inta+1==int(b)):
    print(':(')
else:
    print(inta+1)

Solution (Python):
import math

N = int(input())

A = N/1.08
B = (N+1)/1.08

if(A.is_integer()):
    print(math.floor(A))
else:
    if(B.is_integer()):
        print(":(")
    else:
        if(math.floor(A) == math.floor(B)):
            print(":(")
        else:
            print(math.floor(B))

Solution (Python):
N=int(input())
A=[]
for i in range(50001):
  A.append(int(i*1.08//1))
if N in A:
  print(int((N+0.99)/1.08))
else:
  print(":(")

Solution (Python):
a = int(input())
b = int(a//1.08)
c = b+1
if int(b*1.08) == a:
	print(b)
elif int(c*1.08) == a:
	print(c)
else:
	print(":(")

Solution (Python):
import math as m

n = int(input())

x = n / 1.08
x1 = round(x, 0)

n1 = m.floor(x1 * 1.08)
n2 = m.floor((x1+1) * 1.08)



if x == x1:
    print(int(x))
elif n1 == n:
    print(int(x1))
elif n2 == n:
    print(int(x1+1))
elif n1 < n < n2:
    print(':(')

Solution (Python):
from fractions import gcd

from heapq import*
import math
from collections import defaultdict, Counter, deque
import sys
from bisect import *
import itertools
import copy
sys.setrecursionlimit(10 ** 7)
MOD = 10 ** 9 + 7


def main():
    n = int(input())
    v = math.ceil(n / 1.08)
    vv = v * 1.08
    
    if n == math.floor(vv):
        print(v)
    else:
        print(":(")


    


if __name__ == '__main__':
    main()

Solution (Python):
import math
n = int(input())
a = round(n / 1.08)
c = a + 1
b = int(a *1.08)
d = int(c *1.08)
if b == n:
    print(a)
elif d == n:
    print(c)
else:
    print(':(')

Solution (Python):
import math
n = int(input())
ans = 0
ng = 0
for i in range(1,50001):
    if math.floor(i*1.08) == n:
        ans = i
    else:
        continue
if ans == 0:
    print(':(')
else:
    print(ans)

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

for i in range(1, n+1):
  if n <= i*1.08 <n+1:
    print(i)
    break
else:
  print(':(')

Solution (Python):
n=int(input())
x = int(n / 1.08)
if int(x * 1.08) == n:
  print(x)
elif int((x+1) * 1.08) == n:
  print(x+1)
else:
  print(':(')

Solution (Python):
N = int(input())
Z = int(N/1.08)

for i in range(Z,Z+2):
    if N/1.08 <= i < (N+1)/1.08:
        if int(N/1.08) == int((N+1)/1.08):
            print(Z)
            break
        else:
            print(Z+1)
            break
else:
    print(":(")

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

ans = int(n / 1.08)
start_search = ans - 500
end_search = ans + 500

for i in range(start_search, end_search):
    a = int(i * 1.08)
    if a == n:
        print(i)
        exit()

print(":(")

Solution (Python):
N = int(input())
Y = N / 1.08
if Y == int(Y):
  print(int(Y))
elif int((int(Y) + 1) * 1.08) == N:
  print(int(Y) + 1)
else:
  print(':(')

Solution (Python):
N = int(input())
ans = 0
k = 0
for i in range(N+1):
    if N<=i*1.08<N+1:
        print(int(i))
        ans += 1
        break
if ans == 0:
    print(":(")

Solution (Python):
n = int(input()) * 25
r = (n + 24)//27
print((r, ':(')[r * 27 < n])

Solution (Python):
import math

n = int(input())

x = n / float(1.08)
chk = x - int(x)
if chk > 0:
    tmp = int(x) + 1
    if math.floor(tmp * 1.08) == n:
        print(tmp)
    else:
        print(':(')
else:
    print(int(x))

Solution (Python):
from decimal import Decimal
n=int(input())
ans=':('
for i in range(1,n+1):
  k=i*1.08
  if Decimal(k)//1==n:
    ans=i
    break
print(ans)

Solution (Python):
N= int(input())
X1 = N / 1.08
X = int(X1)
N_calc = int(X*1.08)
N_calc2 = int((X+1)*1.08)
if N_calc == N :
    print(X)
elif N_calc2==N:
    print(X+1)
else :
    print(":(")

Solution (Python):
n = int(input())
for x in range(46297):
  if (x+1)*1.08//1 == n:
    print(x+1)
    break
  if x == 46296:
    print(':(')

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

X_tmp = math.ceil(N/1.08)
if math.floor(X_tmp*1.08) == N:
    print(X_tmp)
else:
    print(':(')

Solution (Python):
import math

N = int(input())

NN = math.floor(N / 1.08)

NNN = math.floor(NN*1.08)

if N == NNN:
    print(NN)
else:
    if math.floor((NN+1)*1.08) == N:
        print(NN+1)
    else:
        print(':(')

Solution (Python):
N = int(input())
if N/1.08 == -(-N//1.08):
    print(int(N/1.08))

else:
    if not -(-N//1.08) == -(-(N+1)//1.08):
        print(int((N+1)//1.08))
    else:
        print(':(')

Solution (Python):
import math

n = int(input())

zeinuki = math.floor(n / 1.08)
zeikomi = math.floor(zeinuki * 1.08)

if zeikomi == n:
    print(zeinuki)
elif zeikomi > n:
    if math.floor((zeinuki-1) * 1.08) == n:
        print(zeinuki-1)
    else:
        print(":(")
elif zeikomi < n:
    if math.floor((zeinuki+1) * 1.08) == n:
        print(zeinuki+1)
    else:
        print(":(")

Solution (Python):

from math import floor

def solve():
    N = int(input())
    for x in range(1, 50001):
        if floor(x*1.08) == N:
            return str(x)
    return ':('

if __name__ == '__main__':
    print(solve())

Solution (Python):
import math
DEBUG_FREE = False
N = int(input())

tax_free_f = N/1.08
tax_free_int = math.ceil(tax_free_f)

if DEBUG_FREE:
    print("float    : %f"%tax_free_f)
    print("int      : %d"%tax_free_int)
    print("recover_f: %f"%(tax_free_int*1.08))
    print("recover_i: %d"%(int(tax_free_int * 1.08)))
    
if N == int(tax_free_int * 1.08):
    print(tax_free_int)
else:
    print(":(")

Solution (Python):
N=int(input())
for i in range(N+1):
    if int(i*1.08)==N:
        print(i)
        break
else:
    print(":(")

Solution (Python):
import math

n = int(input())

for i in range(math.floor(n * 0.9), n+1):
	if n ==  math.floor(i*1.08):
		print(i)
		exit()
print(':(')

Solution (Python):
def main():
    N = float(input())
    nuki = int(N//1.08)
    if int(nuki*1.08)==N:
        print(nuki)
    elif int((nuki+1)*1.08)==N:
        print(nuki+1)
    else:
        print(":(")
        
if __name__=='__main__':
    main()

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

done = False
for i in xrange(1, 50001):
    if int(i * 1.08) == n:
        ans = i
        done = True
        break

if not done:
    ans = ":("

print ans

Solution (Python):
n = int(input())
j = int(n / 1.08 )

if int(j*1.08) == n:
    print(j)
elif int((j+1)*1.08) == n:
    print(j+1)
elif int((j-1)*1.08) == n:
    print(j-1)
else:
    print(":(")

Solution (Python):
n = int(input())
ans = -int(-(n/1.08)//1)
if int(ans * 1.08 // 1) == n:
  print(ans)
else:
  print(':(')

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

latest_num = (N + 1) // 1.08

y = 1.08 * latest_num

if N <= y:
    print(int(latest_num))
else:
    print(":(")

Solution (Python):
import math

n = int(input())

x = n/1.08
t = math.floor(x*1.08)

for i in range(50010):
  if math.floor(i*1.08) == n:
    print(i)
    break
  if i == 50009:
    print(':(')

Solution (Python):
import math
import sys
N = int(input())
Xi = math.ceil(N / 1.08)

for x in range(Xi - 10, Xi + 10):
    if math.floor(x * 1.08) == N:
        print(x)
        sys.exit(0)
print(':(')

Solution (Python):
n=int(input())
ans=-1
for i in range(1,50000):
  if n<=i*1.08 and n+1>i*1.08:
    ans=i
    break
if ans==-1:
  print(":(")
else:
  print(ans)

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

M_1 = (N+1)/1.08
M_2 = (N)/1.08
if M_2 - int(M_2) == 0 :
    print(int(M_2))
else :
    if math.floor(math.ceil(M_2) * 1.08 ) == N :
        print(math.ceil(M_2))
    else :
        print(':(')

Solution (Python):
import math

N = int(input())

X = math.floor(N / 1.08)

for i in range(2):
    ans = X+i
    if (math.floor(ans * 1.08) == N):
        print(ans)
        exit()
print(':(')

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

a = N/1.08

if a == int(a):
    print(int(a))
else:
    a = int(a) + 1
    if int(a*1.08) == N:
        print(a)
    else:
        print(":(")

Solution (Python):
import math

n = int(input())

for x in range(1,50000):
    ans = math.floor(x*1.08)
    if ans == n:
        print(x)
        exit()

print(':(')

Solution (Python):
import math
N = int(input())
Ans = 0

if N % 27 == 13 or N % 27 == 26:
  print(':(')
else:
  Ans = N * 100 / 108
  A = math.ceil(Ans)
  print(A)

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

tax = 1.08
x = n // tax
y = x + 1


if int(x * tax) == n:
    print(int(x))
    exit()

if int(y * tax)== n:
    print(int(y))
    exit()

print(":(")

Solution (Python):
import math

n = int(input())

max = 50000
herf = 25000

arr = []
result = ':('

for t in range(50000):
  arr.append(t)

if herf > n:
  for s in range(herf):
    ans = math.floor(s * 1.08)
    if ans == n:
      result = str(s)
      break;
else:
  for s in range(25000, max):
    ans = math.floor(s * 1.08)
    if ans == n:
      result = str(s)
      break;

print(result)

Solution (Python):
import math
pay = int(input())
est_price = math.ceil(pay/1.08)


if math.floor(est_price * 1.08) == pay:
  print(est_price)
else:
  print(":(")

Solution (Python):
input1 = int(input())
ans = int(input1 / 1.08)
ans2 = ans+1 
if ans*1.08 == input1 :
    print(ans)
elif int((ans2)*1.08) == input1:
    print(ans2)
else :
    print(":(")

Solution (Python):
def main():
  N = int(input())
  X = 1
  
  for X in range(50000):
    if int(X * 1.08) == N:
      return X
  return ":("

print(main())

Solution (Python):
n = int(input())
for i in range(1, n+1):
    if int(i*1.08)==n:
        print(i)
        break
else:print(":(")

Solution (Python):
n=int(input())
x=int(n//1.08+1)
if n==int(x*1.08):
  print(x)
else:
  print(":(")

Solution (Python):
import sys
from math import factorial
from fractions import Fraction
import heapq, bisect
import math
import itertools
sys.setrecursionlimit(10 ** 5 + 10)
INF = 10**15 +5
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()))
MOD = 10**9 + 7

n = INT()
if int(n*100/108) < int((n+1)*100/108) and (n+1)*100 %108 != 0:
    print(math.ceil(n*100/108))
elif n*100 % 108 == 0:
    print(n*100//108)
else:
    print(':(')

Solution (Python):
N=int(input())
ans = -1

for i in range(50000+10):
 x1 = int(i*1.08)
 x2 = i*1.08
 
 if(x1 == N): ans = i
 elif(x2 == N): ans = i
  
  
if(ans == -1):
 print(':(')
else:
 print(ans)

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

x = n / 1.08
x_p = math.floor(x) + 1
x_n = math.floor(x) - 1


if x%1 == 0:
    print(int(x))
else:
    if math.floor(x_p * 1.08) == n:
        print(math.floor(x_p))
    elif math.floor(math.floor(x) * 1.08) == n:
        print(math.floor(x))
    elif math.floor(x_n * 1.08) == n:
        print(math.floor(x_n*1.08))
    else:
        print(':(')

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

a=N//1.08
b=N//1.08+1

a_=math.floor(a*1.08)
b_=math.floor(b*1.08)

if a_==N:
    print(math.floor(a))
elif b_==N:
    print(math.floor(b))
else:
    print(':(')

Solution (Python):
import math

paid = int(input())
price = int(paid/1.08)

if math.floor(price*1.08) == paid:
  print(price)
elif math.floor((price+1)*1.08) == paid:
  print((price+1))
else:
  print(":(")

Solution (Python):
import sys
n = int(input())
start = int(n//1.1)
lis = []
for i in range(start,n+1):
    lis.append(i)
new_lis = []
for l in lis:
    new_lis.append(int(l*1.08))
if n in new_lis:
    for li in lis:
        if int(li*1.08) == n:
            print(li)
            sys.exit()
else:
    print(":(")

Solution (Python):
def main():
    from math import floor
    N = int(input())
    for i in range(50000):
        if floor(i*1.08) == N:
            return print(i)
    else:
        print(":(")


if __name__ == '__main__':
    main()

Solution (Python):
n = int(input())
x = n * 25
if x % 27 == 0:
    x //= 27
else:
    x = x // 27 + 1
if x * 27 // 25 == n:
    print(x)
else:
    print(":(")

Solution (Python):
import sys
from math import ceil, floor

input = sys.stdin.readline


def main():
    n = int(input())
    x = n / 1.08
    if n == floor(ceil(x) * 1.08):
        print(ceil(x))
    elif n == floor(floor(x) * 1.08):
        print(floor(x))
    else:
        print(":(")


if __name__ == "__main__":
    main()

Solution (Python):
import math

X = int(input())

notax = math.ceil(X / 1.08)

if notax < (X + 1) / 1.08:
    print(notax)
else:
    print(':(')

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

X = int(N / 1.08)

ans = -1
while int(X * 1.08) <= N:
    if int(X * 1.08) == N:
        ans = X
    X += 1
    
if ans > 0:
    print(ans)
else:
    print(":(")

Solution (Python):


N = int(input())
A = int(N / 1.08)
B = int(N / 1.08 + 1)



if int(A * 1.08) == N:
    print(int(A))
elif int(B * 1.08) == N:
    print(int(B))

else:
    print(":(")

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

for i in range(1, n+1):
	if int(i*(1.08)) == n:
		print(i)
		exit(0)
print(":(")

Solution (Python):
import math

N = int(input())
X = math.floor(N/1.08)
while X < N/1.08 + 1/1.08:
  if N/1.08 <= X  and X < N/1.08 + 1/1.08:
    X = X
    break
  else:
    X = X+1
 
    
if (N+1)%27 == 0 or (N+14)%27 == 0:
  print(':(')
else:
  print(X)

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

x1 = (n / 1.08)//1
x2 = x1 + 1

if (x1 * 1.08)//1 == n:
    print(int(x1))
elif (x2 * 1.08)//1 == n:
    print(int(x2))
else:
    print(":(")

Solution (Python):
import sys
from decimal import Decimal, ROUND_HALF_UP
import math
input = sys.stdin.readline


def main():
    """code here"""
    N = int(input())
    for i in range(N+1):
        if int(math.floor(i*1.08))==N:
            print(i)
            exit()
    print(":(")
if __name__ == '__main__':
    main()

Solution (Python):
import math
N=int(input())
Min=N/1.08
Max=(N+1)/1.08
Mi=int(math.ceil(Min))
Ma=int(math.floor(Max))
if Mi==Max:
  print(":(")
elif Ma<Mi:
  print(":(")
else:
  print(Mi)

Solution (Python):
import math
n = int(input())
x = int(n // 1.08)
a = [x - 1, x , x +1]

ans = ':('
for i in a:
    if int(math.floor(i * 1.08))  == n:
        ans = i
        break

print(ans)

Solution (Python):
import math
c = int(input())
up  = int(math.ceil(c/1.08))
down = int(math.floor(up*1.08))
print(up if c==down else ':(')