#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string s) {
   int a1=0,a2=0,a3=1,a4=0,a5=0;
    int ctr=0;
    if(n<6)
        a3=0;
    else
        a3=1;
        
    for(int i=0;i<n;i++)
    {
        if(s[i]>=65&&s[i]<=90)
            a1=1;
        else if(s[i]>=97&&s[i]<=122)
            a2=1;
        else if(s[i]>=33&&s[i]<=45&&s[i]!=44&&s[i]!=39&&s[i]!=34)
            a4=1;
        else if(s[i]==64)
            a4=1;
         else if(s[i]>=48&&s[i]<=57)
            a5=1;
        
    }
    if(!a1)
        ctr++;
    if(!a2)
        ctr++;
   
    if(!a4)
        ctr++;
    if(!a5)
        ctr++;
    if(n+ctr<6)
        ctr+=(6-n-ctr);
    return ctr;
}

int main() {
    int n;
    cin >> n;
    string password;
    cin >> password;
    int answer = minimumNumber(n, password);
    cout << answer << endl;
    return 0;
}