#include <bits/stdc++.h>

using namespace std;

int minimumNumber(int n, string p) {
    int m;
    int a = 1 , b = 1, c = 1 , d = 1;
    for (int i = 0; i < p.length(); i++){
        if ('a' <= p[i] && p[i] <= 'z') a = 0;
        if ('0' <= p[i] && p[i] <= '9') d = 0;
        if ('A' <= p[i] && p[i] <= 'Z') b = 0;
        if (p[i] == '!' || p[i] == '@' || p[i] == '#' || p[i] == '$' || p[i] == '%' || p[i] == '+' ||
            p[i] == '^' || p[i] == '&' || p[i] == '*' || p[i] == '(' || p[i] == ')' || p[i] == '-') c = 0;
    }
    int k = 6 - p.length();
    m = max(k , a + b + c + d);
    return m;
}

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