#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    int n;
    string s;
    cin>>n>>s;
    int num_upper=0,num_lower=0,num_digits=0,num_else=0;
    for(int i=0;i<n;i=i+1){
        if(s[i]>64&&s[i]<91){
            num_upper+=1;
        }else if(s[i]>47&&s[i]<58){
            num_digits+=1;
        }else if(s[i]>96&&s[i]<123){
            num_lower+=1;
        }else{
            num_else+=1;
        }
    }
    int count=0;
    if(num_upper==0){
        count+=1;
        n+=1;
    }if(num_lower==0){
        count+=1;
        n+=1;
    }if(num_digits==0){
        count+=1;
        n+=1;
    }if(num_else==0){
        count+=1;
        n+=1;
    }
    if(n<6){
        cout<<count+6-n;
    }else{
        cout<<count;
    }
    return 0;
}