#include <bits/stdc++.h>

using namespace std;
bool containsDigit(string s){
    int i,l = s.length();
    for(i=0;i<l;i++){
        if(s[i]>='0'&&s[i]<='9')
            return true;
    }
    return false;
}
bool containsUpper(string s){
    int i,l = s.length();
    for(i=0;i<l;i++){
        if(s[i]>='A'&&s[i]<='Z')
            return true;
    }
    return false;
}

bool containsLower(string s){
    int i,l = s.length();
    for(i=0;i<l;i++){
        if(s[i]>='a'&&s[i]<='z')
            return true;
    }
    return false;
}
bool containsChar(string s){
    int i,l=s.length();
    //!@#$%^&*()-+
    for(i=0;i<l;i++){
        if(s[i]=='#')
            return true;
        if(s[i]=='!')
            return true;
        if(s[i]=='@')
            return true;
        if(s[i]=='$')
            return true;
        if(s[i]=='%')
            return true;
        if(s[i]=='^')
            return true;
        if(s[i]=='&')
            return true;
        if(s[i]=='*')
            return true;
        if(s[i]=='(')
            return true;
        if(s[i]==')')
            return true;
        if(s[i]=='-')
            return true;
        if(s[i]=='+')
            return true;
    }
    return false;
}
int minimumNumber(int n, string password) {
    // Return the minimum number of characters to make the password strong
    int i,l=password.length();
        
    int c=0;
    c = !containsChar(password) + !containsDigit(password) + !containsUpper(password) + !containsLower(password);
    if(n+c < 6)
       return c + 6-(n+c);
    return c;
}

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