#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string password) {
    // Return the minimum number of characters to make the password strong
    int req=4;
   // bool digit=false,lower=false,upper=false,special=false;
    for(int i=0;password[i]!='\0';i++)
    {
        if(password[i]>=48&&password[i]<=57) {req--;break;}
    }
    for(int i=0;password[i]!='\0';i++)
    {
        if(password[i]<=90&&password[i]>=65) {req--;break;}
    }
    for(int i=0;password[i]!='\0';i++)
    {
        if(password[i]<=122&&password[i]>=97) {req--;break;}
    }
    for(int i=0;password[i]!='\0';i++)
    {
        if(password[i]=='!'||password[i]=='@'||password[i]=='$'||password[i]=='%'||password[i]=='^'||password[i]=='&'||password[i]=='*'||password[i]=='('||password[i]==')'||password[i]=='-'||password[i]=='+'||password[i]=='"'||password[i]=='#') {req--;break;}
    }
   return max(req,6-n);    
        
     
}

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