You can not just take the file and send it. When Polycarp trying to send a file in the social network "Codehorses", he encountered an unexpected problem. If the name of the file contains three or more "x" (lowercase Latin letters "x") in a row, the system considers that the file content does not correspond to the social network topic. In this case, the file is not sent and an error message is displayed.

Determine the minimum number of characters to remove from the file name so after that the name does not contain "xxx" as a substring. Print 0 if the file name does not initially contain a forbidden substring "xxx".

You can delete characters in arbitrary positions (not necessarily consecutive). If you delete a character, then the length of a string is reduced by 1. For example, if you delete the character in the position 2 from the string "exxxii", then the resulting string is "exxii".

Input

The first line contains integer n (3 ≤ n ≤ 100) — the length of the file name.

The second line contains a string of length n consisting of lowercase Latin letters only — the file name.

Output

Print the minimum number of characters to remove from the file name so after that the name does not contain "xxx" as a substring. If initially the file name dost not contain a forbidden substring "xxx", print 0.

Examples

Input

6
xxxiii


Output

1


Input

5
xxoxx


Output

0


Input

10
xxxxxxxxxx


Output

8

Note

In the first example Polycarp tried to send a file with name contains number 33, written in Roman numerals. But he can not just send the file, because it name contains three letters "x" in a row. To send the file he needs to remove any one of this letters.
# ------------------- fast io --------------------
import os
import sys
from io import BytesIO, IOBase
#sys.setrecursionlimit(10**5)

BUFSIZE = 8192


class FastIO(IOBase):
    newlines = 0

    def __init__(self, file):
        self._fd = file.fileno()
        self.buffer = BytesIO()
        self.writable = "x" in file.mode or "r" not in file.mode
        self.write = self.buffer.write if self.writable else None

    def read(self):
        while True:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            if not b:
                break
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines = 0
        return self.buffer.read()

    def readline(self):
        while self.newlines == 0:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            self.newlines = b.count(b"\n") + (not b)
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines -= 1
        return self.buffer.readline()

    def flush(self):
        if self.writable:
            os.write(self._fd, self.buffer.getvalue())
            self.buffer.truncate(0), self.buffer.seek(0)


class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        self.write = lambda s: self.buffer.write(s.encode("ascii"))
        self.read = lambda: self.buffer.read().decode("ascii")
        self.readline = lambda: self.buffer.readline().decode("ascii")


sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda: sys.stdin.readline().rstrip("\r\n")
if os.path.exists('input.txt'):
    sys.stdin = open('input.txt','r')
    sys.stdout = open('output.txt','w')


# ------------------- fast io --------------------
from math import *
from itertools import * # chain,groupby,permutations,combinations
from collections import Counter
from bisect import *

"""
def prod(a, mod=10**9+7):
    ans = 1
    for each in a:
        ans = (ans * each) % mod
    return ans

def lcm(a, b): return a * b // gcd(a, b)

def binary(x, length=16):
    y = bin(x)[2:]
    return y if len(y) >= length else "0" * (length - len(y)) + y


def powerset(s):
    n=len(s)
    
    return chain.from_iterable(combinations(s,r) for r in range(1,n))

def binarySearch(arr,x): 
    l=0
    r=len(arr)-1
    while l <= r: 
  
        mid = l + (r - l) // 2; 
        if arr[mid] == x: 
            return mid 
        elif arr[mid] < x: 
            l = mid + 1
        else: 
            r = mid - 1
    return -1

def prime(): #array of prime numbers
    arr = [1]*10000
    for i in range(10000):
        if i==0:
            arr[i]=0
        elif i==1:
            arr[i]=0
        else:
            if not arr[i]:
                continue
            j=i
            for k in range(2,10000):
                if j*k>=len(arr):
                    break
                arr[j*k]=0
    return arr

def isprime(x) -> bool: #return true if number is prime
    i=2
    while i*i<=x:
        if x%i==0:
            return 0
        i+=1
    return 1


def palindrome(string,start,end):
    if start==end:
        return True
    if end==1:
        return True
    return string[start]==string[end-1] and palindrome(string,start+1,end-1)


"""

#----#




def aa(): #for int
    return(int(input()))
def bb(): #for int arr
    return(list(map(int,input().split())))
def cc():  #for string
    s = input()
    return (list(s))
def dd(): #space seperated intege
    return(map(int,input().split()))
#----#


def koi_coding_sikha_do():
   
    n=aa()
    s = cc()
    temp = [s[0],s[1]]
    count=0
    for i in range(2,n):
        if s[i]=="x":
            if temp[-1]=="x" and temp[-2]=="x":
                count+=1
            else:
                temp.append("x")
        else:
            temp.append(s[i])
    print(count)






         
if __name__ == "__main__":
    t=1#aa()
    while(t):
        koi_coding_sikha_do()
        t-=1



"""

__________          __  .__                              __    __             _________                          
\______   \___.__._/  |_|  |__   ____   ____             \ \   \ \            \_   ___ \     .__         .__     
 |     ___<   |  |\   __\  |  \ /  _ \ /    \             \ \   \ \           /    \  \/   __|  |___   __|  |___ 
 |    |    \___  | |  | |   Y  (  <_> )   |  \            / /   / /           \     \____ /__    __/  /__    __/ 
 |____|    / ____| |__| |___|  /\____/|___|  /           /_/   /_/             \______  /    |__|        |__|    
           \/                \/            \/                                         \/                         

Unke aakhon me aasu aur chahre pe hasi hai......lagta hai unki lulli unki zip me phasi hai
"""

