#define _CRT_SECURE_NO_WARNINGS 1
#include <iostream>
#include<string>
#include<cstdio>
using namespace std;
int main()
{
	int n, a, b, c,w=0,s=0;
	string dt;
	cin >> n;
	cin >> dt;
	b = dt.find("vv");
	c = dt.find("kk");
	if ((b >= 0 && b <= dt.size()) || (c >= 0 && c <= dt.size()))
		w = 1;
	while (dt.find("vk")>=0&& dt.find("vk")<=dt.size()){
		a = dt.find("vk");
		dt = dt.substr(a + 2, dt.size());
		s++;
	}
	cout << s + w;
	return 0;
}