#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string s) {
    string sp = "!@#$%^&*()-+";
    int x = 1, l=1, u=1, y=1;
    for(int i=0;i<s.size();i++) {
        int flag = 0;
        for(int j=0;j<sp.size();j++)
            if( sp[j] == s[i] ) y = 0;
        if( 'a' <= s[i] && s[i] <= 'z' ) l = 0;
        if( 'A' <= s[i] && s[i] <= 'Z' ) u = 0;
        if( '0' <= s[i] && s[i] <= '9' ) x = 0;
    }
    return max( x+l+u+y, (int)(6-s.size()) );
}

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