#include <bits/stdc++.h>

using namespace std;

int main() {
    int n;
    cin >> n;
    string s;
    cin >> s;
    string s1 = "!@#$%^&*()-+";
    set <int> se;
    for(int i = 0; i < s1.size(); i++)
    se.insert(s1[i]);
    
    int cond1 = 1;
    int cond2  = 1, cond3 = 1, cond4 = 1;
    
    for(int i = 0; i < s.size(); i++){
        if(s[i] <='9' && s[i] >= '0') cond1 = 0;
        if(s[i] >= 'a' && s[i] <= 'z') cond2 = 0;
        if(s[i] >= 'A' && s[i] <= 'Z') cond3 = 0;
        if(se.count(s[i])) cond4 = 0;
    }
    
    int ans = cond1+cond2+cond3+cond4;
    int ans1 = 6 - s.size();
    
    cout << max(ans1, ans);
    
    
    return 0;
}