#include <bits/stdc++.h>
using namespace std;

string numbers = "0123456789", lower_case = "abcdefghijklmnopqrstuvwxyz", upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ", special_characters = "!@#$%^&*()-+";

int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */ 
    string s;
    int i, j, n, ans = 0;
    cin >> n;
    cin >> s;
    bool ok1 = false, ok2 = false, ok3 = false, ok4 = false;
    for(i = 0; i < numbers.length(); ++i) {
        if(s.find(numbers[i]) != string :: npos)    ok1 = true;
    }
    if(!ok1)    ans++;
    for(i = 0; i < lower_case.length(); ++i) {
        if(s.find(lower_case[i]) != string :: npos)    ok2 = true;
    }
    if(!ok2)    ans++;
    for(i = 0; i < upper_case.length(); ++i) {
        if(s.find(upper_case[i]) != string :: npos)    ok3 = true;
    }
    if(!ok3)    ans++;
    for(i = 0; i < special_characters.length(); ++i) {
        if(s.find(special_characters[i]) != string :: npos)    ok4 = true;
    }
    if(!ok4)    ans++;
    if(n < 6) {
        if(n + ans < 6) {
            cout << 6 - n << endl; 
        }
        else    cout << ans << endl;
        return 0;
    }
    cout << ans << endl;
    return 0;
}