#include <stdio.h>
#include <string.h>
int main ()
{
    int n,cnt=0;
    scanf ("%d",&n);
    char s[n+1];
    scanf ("%s",s);
    for (int i=0;i<n-1;i++)
    {
        if (s[i]=='v'&&s[i+1]=='k') cnt++;
    }
    for (int i=0;i<n-1;i++)
    {
    	if(s[i]=='v'&&s[i+1]=='v')
    	{
            cnt++;
    		break;
		}
		else if(s[i]=='k'&&s[i+1]=='k')
		{
			cnt++;
			break;
		}
	}
    printf ("%d",cnt);
    return 0;
}