#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    int n; cin >> n;
    string s; cin >> s;
    int num = 1, lower = 1, upper = 1, sp = 1;
    for (int i = 0; i < n; i++) {
        if (s[i] >= '0' && s[i] <= '9') {
            num = 0;
        } else if (s[i] >= 'a' && s[i] <= 'z') {
            lower = 0;
        } else if (s[i] >= 'A' && s[i] <= 'Z') {
            upper = 0;
        } else {
            sp = 0;
        }
    }
    int w = 0;
    if (n < 6) {
        int a = 6 - n;
        w = 6 - n;
        if (a > 0 && lower > 0) {
            lower--;a--;
        }
                if (a > 0 && upper > 0) {
            upper--;a--;
        }
                if (a > 0 && sp > 0) {
            sp--;a--;
        }
                        if (a > 0 && num > 0) {
            num--;a--;
        }
    }
    cout <<w+ num + lower + upper + sp << endl;
    return 0;
}