Given is a string S of length N consisting of lowercase English letters.
Snuke can do this operation any number of times: remove fox occurring as a substring from s and concatenate the remaining parts of s.
What is the minimum possible length of s after some number of operations by Snuke?

-----Constraints-----
 - 1 \leq N \leq 2 \times 10^{5}
 - s is a string of length N consisting of lowercase English letters.

-----Input-----
Input is given from Standard Input in the following format:
N
s

-----Print-----
Print the minimum possible length of s after some number of operations by Snuke.

-----Sample Input-----
6
icefox

-----Sample Output-----
3

 - By removing the fox at the end of icefox, we can turn s into ice.

Difficulty: interview

Starter code:

Solutions:
import sys
readline = sys.stdin.readline

# fが来たらstackに[0]をappendする。
# oが来たとき、最後尾が[0]だったら[1]にする
# xが来たとき、最後尾が[1]ならpopする。このとき3を引く

N = int(readline())
S = readline().rstrip()

ans = N
stack = []

for s in S:
  if s == "f":
    stack.append(0)
  elif s == "o":
    if stack and stack[-1] == 0:
      stack[-1] = 1
    else:
      # 最後がfでない状態でoが来た時、このoが消えることはない。
      stack = []
  elif s == "x":
    if stack and stack[-1] == 1:
      stack.pop()
      ans -= 3
    else:
      stack = []
  else:
    stack = []
      
print(ans)

input()
a=input()
res = ""
for c in a:
	res += c
	if res.endswith("fox"):
		res = res[:-3]
print(len(res))

N=int(input())
S=input()
T=""
for s in S:
  if s in "fox":
    T+=s
    if T[-3:]=="fox":
      T=T[:-3]
      N-=3
  else:
    T=""
print(N)

from collections import deque


def remove_fox(stack):
    if len(stack) < 3:
        return
    p1, p2, p3 = stack.pop(), stack.pop(), stack.pop()
    jd = p3 + p2 + p1
    if jd != "fox":
        stack.append(p3)
        stack.append(p2)
        stack.append(p1)


def __starting_point():
    n = int(input())
    s = input()
    t = deque()
    for si in s:
        t.append(si)
        remove_fox(t)
    print((len(t)))

__starting_point()

n=int(input())
s=input()
s2=[]
for i in range(n):
    s2.append(s[i])
    while len(s2) > 2:
        if s2[-1] == 'x' and s2[-2]=='o' and s2[-3] == 'f':
            s2.pop()
            s2.pop()
            s2.pop()
        else:
            break
while len(s2) > 2:
        if s2[-1] == 'x' and s2[-2]=='o' and s2[-3] == 'f':
            s2.pop()
            s2.pop()
            s2.pop()
        else:
            break
print(len(s2))

n = int(input())
s = input()

t = ''
for c in s:
    t += c
    if t[-3:] == 'fox':
        t = t[:-3]

print(len(t))

N = int(input())
s = input()

i = 0
while i < len(s) - 2:
  if s[i:i+3] == "fox":
    s = s[:i] + s[i+3:]
    i -= 2
  else:
    i += 1

print(len(s))

N=int(input())
array=input()
trash=[]
count=0
for i in range(N):
	trash.append(array[i])
	count+=1
	if count>=3:
		if trash[-1]=='x' and trash[-2]=='o' and trash[-3]=='f':
			del trash[-1]
			del trash[-1]
			del trash[-1]
			count-=3
print(count)

N = int(input())
s = input()

que = []
for i in range(N):
    que.append(s[i])
    if len(que) >= 3 and que[-3:] == ['f', 'o', 'x']:
        que.pop()
        que.pop()
        que.pop()
print((len(que)))


n = int(input())
s = input()

t = ""
for i in range(n):
    t += s[i]
    #print("t1 = " + t)
    while len(t) >= 3 and t[-3:] == "fox":
        t = t[:-3]
        #print("t2 = " + t)
print((len(t)))


N = int(input())
r = []
for i in list(input()):
    r.append(i)
    while 1:
        if 3 <= len(r) and r[len(r)-3:] == ["f", "o", "x"]:
            for j in range(3):
                r.pop()
        else:
            break
print(len(r))

N = int(input())
S = list(input())

L = []
for s in S:
    if len(L) >= 2 and s == 'x':
        if L[-2] == 'f' and L[-1] == 'o':
            L.pop()
            L.pop()
        else:
            L.append(s)
    else:
        L.append(s)

print(len(L))

#!/usr/bin/env python
# coding: utf-8

# In[ ]:


n=int(input())
s=input()
ans=''
for i in s:
  ans+=i
  if ans[-3:]=='fox': ans=ans[:-3]
print((len(ans)))



from collections import deque

n = int(input())
S = input()

index = 0
cnt = 0

q = deque()
q.append(index)

for s in S:
        
    if(s == "f"):
        index = 1
        q.append(index)
    elif(s == "o"):
        index = q.pop()
        if(index == 1):
            index = 2
        else:
            index = 0
        q.append(index)
    elif(s == "x"):
        index = q.pop()
        if(index == 2):
            cnt += 1
        else:
            index = 0
            q.append(index)
    else:
        index = q.pop()
        index = 0
        q.append(index)
ans = n - 3 * cnt
print(ans)

n = int(input())
s = input()
ls = []
for i in range(n):
    ls.append(s[i])
    if len(ls) > 2:
        if ls[-3] == "f" and ls[-2] == "o" and ls[-1] == "x":
            n-=3
            ls.pop()
            ls.pop()
            ls.pop()
print(n)


n = int(input())
s = input()
tmp = []
for i in s:
    tmp.append(i)
    if len(tmp) >= 3:
        if tmp[-3:] == ["f","o","x"]:
            tmp.pop()
            tmp.pop()
            tmp.pop()
        
print((len(tmp)))


n = int(input())
s = input()
t = []
for i in range(n):
    t.append(s[i])
    if len(t) >= 3 and t[-3:] == ["f", "o", "x"]:
        t.pop()
        t.pop()
        t.pop()
print((len(t)))


input()
a=input()
res = ""
for c in a:
	res += c
	if res.endswith("fox"):
		res = res[:-3]
print(len(res))

n = int(input())
s = input()

t = ""

for c in s:
    t += c
    while len(t) >= 3 and t[-3:] == 'fox':
        t = t[:-3]

print((len(t)))


_ = input()
s1 = list(input())
s2 = []

for c in s1:
    try:
        if c == "x" and s2[-1] == "o" and s2[-2] == "f":
            s2.pop()
            s2.pop()
        else:
            s2.append(c)
    except:
        s2.append(c)
    

print((len(s2)))


n = int(input())
t = input()
s = []
for i in range(n):
	s.append(t[i])
	if len(s) > 2 and s[-3:] == ["f", "o", "x"]:
		for _ in range(3):
			s.pop()
print(len(s))

import sys

# B - Abbreviate Fox
N = int(input())
s = input()
t = ''

for c in s:
  t += c

  if t.endswith('fox'):
    t = t[:len(t)-3]

print(len(t))

input()
a=input()
res = ""
for c in a:
	res += c
	if res.endswith("fox"):
		res = res[:-3]
print(len(res))

N = int(input())
S = input()

R = ''

rep = 'fox'
nxt = 0
ans = 0
for i in range(N):
    found = False
    for k in range(3):
        if S[i] == rep[k]:
            R += rep[k]
            found = True
    if not found:
        R = ''
    if R[-3:] == rep:
        ans += 1
        R = R[:-3]
print((N-ans*3))


ans = int(input())
S = input()
stack = []
for c in S:
    stack.append(c)
    if 3 <= len(stack) and stack[-3] == 'f' and stack[-2] == 'o' and stack[-1] == 'x':
        stack.pop()
        stack.pop()
        stack.pop()
        ans -= 3
print(ans)

n = int(input())
s = list(input())
ans = []
for c in s:
	ans.append(c)
	if ''.join(ans[-3:])=='fox':
		ans.pop()
		ans.pop()
		ans.pop()
print(len(ans))

import sys
readline = sys.stdin.readline

# fが来たらstackに[0]をappendする。
# oが来たとき、最後尾が[0]だったら[1]にする
# xが来たとき、最後尾が[1]ならpopする。このとき3を引く

N = int(readline())
S = readline().rstrip()

ans = N
stack = []

for s in S:
  if s == "f":
    stack.append(0)
  elif s == "o":
    if stack and stack[-1] == 0:
      stack[-1] = 1
    else:
      # 最後がfでない状態でoが来た時、このoが消えることはない。
      stack = []
  elif s == "x":
    if stack and stack[-1] == 1:
      stack.pop()
      ans -= 3
    else:
      stack = []
  else:
    stack = []
      
print(ans)

N=int(input())
S=input()
T=[]
n=0


for s in S:
  T.append(s)
  if T[-3:]==['f','o','x']:
    T.pop()
    T.pop()
    T.pop()
    n+=1
print(len(S)-3*n)

from collections import deque
n = int(input())
s = deque(list(input()))
ans = deque()

while s:
    ans.append(s.popleft())
    if len(ans) >= 3:
        if ans[-3] == 'f' and ans[-2] == 'o' and ans[-1] == 'x':
            for _ in range(3): ans.pop()

print(len(ans))

A = input()
B = input()

if int(A) == len(B):
    x = ''
    for i in B:
        x += i
        if x[-3:] == 'fox':
            x = x[0:len(x)-3]
    print(len(x))

n=int(input())
S=input()

ans=""
for s in S:
    ans+=s
    
    if ans[-3:] == "fox":
        ans=ans[0:-3]
        
print(len(ans))

n = int(input())
s = list(input())
t = []
for i in range(n):
    t.append(s[i])
    if len(t) >= 3 and t[-3] + t[-2] + t[-1] == "fox":
        t.pop(-1)
        t.pop(-1)
        t.pop(-1)
print(len(t))

l = int(input())
text = input()
tgt, ans = 'fox', ''

for i in range(l):
    ans += text[i]
    if ans[-3:] == tgt:
        ans = ans[:-3]
print(len(ans))

N = int(input())
s = input()
t = ''

for i in range(len(s)):
    t += s[i]
    if t.endswith('fox'):
        t = t[:-3]
print((len(t)))


N=int(input())
S=input()
T=""
for s in S:
  T+=s
  if T[len(T)-3:len(T)]=="fox":
    T=T[:len(T)-3]
print(len(T))

N = int(input())
s = str(input())

t = ""

for i in range(N):
    t = t + s[i]
    if t[-3:] == "fox":
        t = t[:len(t)-3]

print(len(t))

def main():
    _ = int(input())
    s = input()

    st = []
    for c in s:
        if c == 'x':
            if len(st) >= 2 and st[-1] == 'o' and st[-2] == 'f':
                for _ in range(2):
                    st.pop()
                continue
        st.append(c)
    ans = len(st)
    print(ans)


def __starting_point():
    main()

__starting_point()

n=int(input())
s=list(input())
from collections import deque
q=deque(s)
p=[]

while q:
  a=q.popleft()
  if a!="x":
    p.append(a)
    continue
  # ここではa==xをみたす
  try:
    f=p[-2]
    o=p[-1]
    if f=="f" and o=="o":
      p.pop()
      p.pop()
      continue
  except:
    pass
  p.append(a)
print(len(p))#,p)

n=int(input())
s=list(input())

from collections import deque
q=deque()

ans=n
for i in range(n):
  q.append(s[i])
  if len(q)<=2:
    continue
  a=q.pop()
  b=q.pop()
  c=q.pop()
  if c+b+a=="fox":
    ans-=3
  else:
    q.append(c)
    q.append(b)
    q.append(a)
 
print(ans)


n = int(input())
s = list(input())

cnt = 0

while True:
    for i in range(cnt, len(s)-2):
        if s[i:i+3] == ['f', 'o', 'x']:
            del s[i:i+3]
            cnt = max(0, i-3)
            break
    else:
        break
    
print((len(s)))


n = int(input())
s = input()
t = ""
for i in range(n):
  t += s[i]
  if t[len(t)-3:] == "fox":
    t = t[:len(t)-3]
print(len(t))

n = int(input())
s = input()

index = 0
while index < n:
  if s[index:index+3] == 'fox':
    s = s[0:index] + s[index+3:len(s)]
    index -= 2
  else:
    index += 1

print(len(s))

def resolve():
    N = int(input())
    S = list(input())
    if N < 3:
        print(N)
    else:
        now = S[:2]
        ans = 0
        for i in range(2, len(S)):
            now.append(S[i])
            #print(now)
            if now[-3:] == ["f", "o", "x"]:
                now.pop()
                now.pop()
                now.pop()
                ans += 3

        print(N-ans)

resolve()

N=int(input())
S=input()

T=""

for i in range(N):
    T=T+S[i]
    if len(T)>2:
        if T[-3]=='f' and T[-2]=='o' and T[-1]=='x':
            T=T[:-3]

print(len(T))

N=int(input())
S=input()


ans=0
que =""

for s in S:
    if s in ["f","o"]:
        que = "".join([que,s])
    elif s=="x":
        if len(que)>=2 and que[-2:]=="fo":
            ans+=1
            que=que[:-2]
        else:
            que=""
    else:
        que=""
    #print(que)
print(N-3*ans)

def main():
    N = int(input())
    S = input()
    stack = []
    cur = 0
    ans = N
    for c in S:
        if c == "f" and cur != 0:
            stack.append(cur)
            cur = 1
        elif c == "f" and cur == 0:
            cur += 1
        elif c == "o" and cur == 1:
            cur += 1
        elif c == "x" and cur == 2:
            ans -= 3
            if len(stack):
                cur = stack.pop()
            else:
                cur = 0
        else:
            cur = 0
            stack = []
    print(ans)


def __starting_point():
    main()

__starting_point()

n = int(input())
s = input()

l = []
for i in range(n):
    l.append(s[i])
    if len(l) >= 3 and ''.join(l[-3:]) == 'fox':
        l.pop()
        l.pop()
        l.pop()

print((len(l)))


n = int(input())
s = input().strip()
from collections import deque

d = deque([])
t = []
ct = 0

for i in s:
    d.append(i)

while len(d) != 0:
    ch = d.popleft()
    t.append(ch)
    if len(t) >= 3 and t[-3:] == ["f", "o", "x"]:
        t.pop()
        t.pop()
        t.pop()
        ct += 1


print((len(t)))


N = int(input())
S = input()
a = ""
for i in range(N):
    a += S[i]
    if len(a)>=3 and a[-3]+a[-2]+a[-1]=='fox':
        a = a[:-3]
print(len(a))

n = int(input())
s = input()
t = ""
cnt = 0
for si in s:
    t += si
    if len(t) >= 3 and t[-3:] == "fox":
        cnt += 1
        t = t[:-3]
print(n - cnt * 3)

def main():
  n = int(input())
  s = str(input())
  num = len(s)
  n = 0
  while True:
    if n+3 > num:
      break
    if s[n:n+3] == "fox":
      s = s[:n] + s[n+3:]
      n = max(0, n-3)
    else:
      n += 1
  print(len(s))
    
def __starting_point():
  main()
__starting_point()

n=int(input())
s=input()

tmp=""
result=0
for word in s:
    tmp+=word
    if tmp[-3:]=="fox":
        result+=1
        tmp=tmp[:-3]
print(len(tmp))

n=int(input())
s=input()
l=[]
l.append(1) #to avoid stack underflow
for i in range(n):
    if l[-1]=="o":
        if l[-2]=="f" and s[i]=="x":
            l.pop()
            l.pop()
        else:
            l.append(s[i])
    else:
        l.append(s[i])
print((len(l)-1))


n=int(input())
s=input()
l=["0"]
for i in s:
	if l[-1]=="o":
		if l[-2]=="f" and i=="x":
			l.pop()
			l.pop()
		else:
			l.append(i)
	else:
		l.append(i)
print(len(l)-1)

n = int(input())
s = list(input())
from collections import deque
ss = deque(s)
t = deque()

for i in range(n):
    p = ss.popleft()
    t.append(p)
    if len(t)>2 and t[-3]=="f" and t[-2]=="o" and t[-1]=="x":
        t.pop()
        t.pop()
        t.pop()
print((len(t)))



n = int(input())
s = input()
cnt = 0
a = []
for i in range(n):
    a.append(s[i])
    if len(a) >=3 and a[-3] == "f" and a[-2] == "o" and a[-1] == "x":
        for _ in range(3):
            a.pop()
print((len(a)))


N=int(input())
s=input()
t=[]
for i in range(N):
  t.append(s[i])
  if len(t)>=3 and t[-3:]==["f","o","x"]:
    t.pop()
    t.pop()
    t.pop()
print(len(t))

n = int(input())
s = str(input())

stack = []
for c in s:
    if c == 'x':
        if len(stack) < 2:
            stack.append(c)
        else:
            if stack[-2] == 'f' and stack[-1] == 'o':
                stack.pop()
                stack.pop()
            else:
                stack.append(c)
    else:
        stack.append(c)
print((len(stack)))


def main():
    import sys
    input = sys.stdin.readline
    N = int(input())
    S = input().strip()
    lenS = len(S)
    i = 1
    while i < lenS-1:
        if S[i] == 'f':
            i += 1
            continue
        if S[i] != 'o':
            i += 2
            continue
        if S[i-1] == 'f' and S[i+1] == 'x':
            lenS -= 3
            S = S[:i-1] + S[i+2:]
            i = max(1, i-2)
        else:
            i += 2
    print(lenS)
   
def __starting_point():
    main()
__starting_point()

n=int(input())
l=list(input())
t=[]
for i in range(n):
    t.append(l[i])
    if len(t)>=3 and t[-3:]==['f','o','x']:
        for j in range(3):
            t.pop()
print(len(t))

n = int(input())
s = input()
t = ""
x = 0
for i in range(n):
  t += s[i]
  x += 1
  if x >= 3 and t[-3:] == "fox":
    t = t[:-3]
    x -= 3

ans = len(t)
print(ans)


N = int(input())
s = input()

t = ''
for i in range(N):
    t += s[i]
    if t.endswith('fox'):
        t = t[:-3]
print(len(t))

N = int(input())
S = input()
a = ""
for i in range(N):
    a += S[i]
    if 'fox' ==a[-3:]:
        a = a[:-3]
print(len(a))

N=int(input())
S="".join(input().split("fox"))
T=""
for s in S:
  T+=s
  if T[len(T)-3:len(T)]=="fox":
    T=T[:len(T)-3]
print(len(T))

from collections import Counter,defaultdict,deque
from heapq import heappop,heappush,heapify
from bisect import bisect_left,bisect_right 
import sys,math,itertools,fractions,pprint
from typing import Union
sys.setrecursionlimit(10**8)
mod = 10**9+7
INF = float('inf')
def inp(): return int(sys.stdin.readline())
def inpl(): return list(map(int, sys.stdin.readline().split()))

n = inp()
s = list(input())
res = []
for i,x in enumerate(s):
    res.append(x)
    ln = len(res)
    if ln >= 3 and res[ln-3:ln] == ['f','o','x']:
        for _ in range(3): res.pop()
print(len(res))

N=int(input())
s=input()

t="";
while len(s):
  t+=s[0]
  s=s[1:]
  if t[-3:]=="fox":
    t=t[:-3]
print(len(t))

N = int(input())
s = list(input())
stack = []
cnt = 0
for i in range(N):
    if s[i] == "f":
        stack.append("f")
    elif s[i] == "o" and len(stack) >= 1:
        if not stack[-1] == "f":
            stack = []
        else:
            stack.append("o")
    elif s[i] == "x" and len(stack) >= 2:
        if stack[-2] == "f" and stack[-1] == "o":
            stack.pop()
            stack.pop()
            cnt += 1
        else:
            stack = []
    else:
        stack = []
print((N - 3*cnt))


n=int(input())
l=list(input())
t=[]
for i in range(n):
    t.append(l[i])
    if len(t)>=3 and t[-3:]==['f','o','x']:
        for j in range(3):
            t.pop()
print(len(t))

N = int(input())
s = input()
t = ""
for n in range(N):
  t += s[n]
  while len(t) >= 3 and t[-3:] == "fox":
    t = t[:-3]
print(len(t))

N = int(input())
s = input()
tmp = ''
for i in s:
    tmp += i
    if len(tmp) >= 3 and tmp[-3] + tmp[-2] + tmp[-1] == 'fox':
        tmp = tmp[:-3]
print(len(tmp))

n=int(input())
s=input()

stk=[]
cnt=0
for i in s:
    if i in ["f","o","x"]:
        stk.append(i)
    else:
        stk=[]

    if i=="x":
        if len(stk)>=3 and stk[-1] == "x" and stk[-2]=="o" and stk[-3] == "f":
            stk.pop()
            stk.pop()
            stk.pop()
            cnt+=1

print(n-3*cnt)

N = int(input())
S = input()
ans = ""

for s in S:
  ans+=s
  if ans[-3:]=="fox":
    ans=ans[:-3]

print(len(ans))

n = int(input())
s = input()

# 解説を見て、分かった。これは思いつかない。
# このような問題をこなさないといけない領域だ。
# いやーなるほど。面白い。

# この変数に代入していく
work = ''

for i in s:
    work += i
    if work[-3:] == 'fox':
        work = work[:-3]
print(len(work))

import sys
input = sys.stdin.readline
N = int(input())

S = input()

cnt = 0
tmp = []
for s in S:
    tmp.append(s)
    if len(tmp) <= 2:
        continue
    else:
        if tmp[-1]=="x" and tmp[-2]=="o" and tmp[-3]=="f":
            cnt += 1
            for _ in range(3):
                tmp.pop()
print((N-cnt*3))


#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# FileName: 	B_fix2
# CreatedDate:  2020-11-21 21:26:09 +0900
# LastModified: 2020-12-04 15:29:40 +0900
#


import os
import sys
# import numpy as np
# import pandas as pd


def main():
    N = int(input())
    S = input()
    T = ""
    for s in S:
        T += s
        if len(T) >= 3 and T[-3:] == "fox":
            T = T[:-3]
    print((len(T)))


def __starting_point():
    main()

__starting_point()

n = int(input())
s = input()

ans = ''

for i in range(n):
    ans += s[i]
    if len(ans) < 3: continue
    if ans[-3:] == 'fox':
        ans = ans[:-3]
print(len(ans))

n = int(input())
s = input()
t = ''
for ss in s:
  t += ss
  if len(t) >=3:
    if t[len(t)-3:len(t)] == 'fox':
      t = t[:len(t)-3]

print(len(t))

n = int(input())
s = str(input())

stack = []
for c in s:
    if c == 'x':
        if len(stack) < 2:
            stack.append(c)
        else:
            if stack[-2] == 'f' and stack[-1] == 'o':
                stack.pop()
                stack.pop()
            else:
                stack.append(c)
    else:
        stack.append(c)
print((len(stack)))


def solve():
    n = int(input())
    s = input()
    stack = []
    for c in s:
        if c == 'x' and len(stack) >= 2 and stack[-1] == 'o' and stack[-2] ==  'f':
            stack.pop()
            stack.pop()
        else:
            stack.append(c)
    print((len(stack)))


solve()


N = int(input())
s = input()

t = ''
for i in range(N):
    t += s[i]
    if t[-3:] == 'fox':
        t = t[:-3]
print(len(t))

n=int(input())
s=input()+"zzz"
t="zzz"
ans=n
cnt=0
for i in range(n):
    if cnt>=n+1:
        break
    if s[cnt:cnt+3]=="fox":
        ans-=3
        cnt+=3
    else:
        t+=s[cnt]
        cnt+=1
        if t[-3:]=="fox":
            ans-=3
            t=t[:-3]
print(ans)


N = int(input())
S = input()

R = ''

rep = 'fox'
nxt = 0
ans = 0
for i in range(N):
    R += S[i]
    if len(R) >= 3 and R[-3:] == rep:
        R = R[:-3]

print((len(R)))


n = int(input())
s = input()

stack = []

for i in range(n):
    stack.append(s[i])
    while stack[-3:] == ['f', 'o', 'x']:
        stack.pop()
        stack.pop()
        stack.pop()
    
print(len(stack))

N = int(input())
S = input()

R = ''

rep = 'fox'
nxt = 0
ans = 0
for i in range(N):
    R += S[i]
    if len(R) >= 3 and R[-3:] == rep:
        R = R[:-3]

print((len(R)))


n = int(input())
s = input()
q = ''
sub = 0
for i in s:
    q += i
    if len(q) >= 3 and q[-3:] == 'fox':
        sub += 3
        q = q[:-3]
print(n - sub)

n = int(input())
s = input()
t = ""

for i in range(n):
  t += s[i]
  if t[len(t)-3:] == "fox":
    t = t[:len(t)-3]
  
print(len(t))

n = int(input())
s = list(input())
a = []
b = 0
for i in s:
  a.append(i)
  b += 1
  if b>2:
    if a[-3:]==["f","o","x"]:
      del a[-3:]
      b-=3
print(b)

N = int(input())
s = input()

t = ''
for i in s:
    t += i
    if t.endswith('fox'):
        t = t[:-3]
print(len(t))

n=int(input())
s=str(input())
ans = 0
t = ""
for i in range(n):
  t += s[i]
  if(len(t)>=3):
    if(t[-3:]=="fox"):
      t = t[0:-3]
      ans += 1
print(n-ans*3)

import sys
readline = sys.stdin.readline

N = int(readline())
S = readline().rstrip()

T = ""

for s in S:
  T += s
  if len(T) >= 3 and T[-3:] == "fox":
    T = T[:-3]
    
print(len(T))

def main():
    N = int(input())
    ans = N
    stack = []
    s = input()
    for c in s:
        if c == "f" or c == "o" or c == "x":
            stack.append(c)
        else:
            stack.clear()
        if c == "x":
            if len(stack) >= 3 and stack[-2] == "o" and stack[-3] == "f":
                ans -= 3
                for i in range(3):
                    stack.pop()
        
    return print(ans) 

def __starting_point():
    main()
__starting_point()

length = int(input())
string = input()
ans = []
for index in range(length):
    if string[index] == "x" and len(ans) >= 2:
        if ans[len(ans)-2] == "f" and ans[len(ans)-1] == "o":
            ans.pop()
            ans.pop()
        else:
            ans.append(string[index])
    else:
        ans.append(string[index])
print(len(ans))

#!/usr/bin/env python

n = int(input())
s = input()

t = ''
cnt = 0 
while len(s) > 0:
    t += s[0]
    s = s[1:]
    if len(t) >= 3 and t[-3:] == 'fox':
        cnt += 1
        t = t[:-3]

ans = n-3*cnt
print(ans)


input()
a=input()
res = ""
for c in a:
	res += c
	if res.endswith("fox"):
		res = res[:-3]
print(len(res))

n = int(input())
s = input()
stack = []
ans = 0
for i in range(n):
    if s[i] == 'f':
        stack.append('f')
    elif s[i] == 'o':
        stack.append('o')
    elif s[i] == 'x':
        if len(stack) >= 2:
            if stack[-1] == 'o' and stack[-2] == 'f':
                ans += 1
                stack.pop()
                stack.pop()
            else:
                stack.clear()
        else:
            stack.clear()
    else:
        stack.clear()
print((n-ans*3))


from collections import deque
n = int(input())
s = input()
l_s = len(s)
cnt = 0
d = deque()
for i in s:
    # print(i,d,cnt)
    if i == "x":
        if len(d) > 1:
            o = d.pop()
            f = d.pop()
            if o == "o" and f == "f":
                cnt += 1

            else:
                d.append(f)
                d.append(o)
                d.append(i)
        else:
            d.append(i)
    else:
        d.append(i)

print(l_s - 3*cnt)

# 解説を見て解いた
# 空文字列に1文字ずつ足していき末尾3文字がfoxなら取り除けばよい

N = int(input())
s = input()

ps = ''

for c in s:
    ps += c
    if ps[len(ps)-3:len(ps)] == 'fox':
        ps = ps[0:len(ps)-3]

print(len(ps))

n = int(input())
s = input()
ss = s[:2]
s = s[2:]
for x in s:
    if ss[-2:] + x == 'fox':
        ss = ss[:-2]
    else:
        ss += x

print(len(ss))