#include<bits/stdc++.h>
using namespace std;
int main()
{ 
    int n;
	char s[100];
	int x=0;
	cin>>n>>s;
	for(int i=0; i<n-1; i++)
	{ 
		if(s[i]=='v'&&s[i+1]=='k')
		{ 
			x++;
			s[i]='y';
			s[i+1]='y';
		} 
	} 
	for (int i=0; i<n-1; i++)
	{
		if(s[i]=='v'&&s[i+1]=='v')
		{
			x++;
			break;
		}
		if(s[i]=='k'&&s[i+1]=='k')
		{
			x++;
			break;
		}
	}
	cout<<x;
}