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


int main() {
    int n;
    cin >> n;
    string s;
    cin >> s;
    
    string constraints[] = { "0123456789",
        "abcdefghijklmnopqrstuvwxyz",
        "ABCDEFGHIJKLMNOPQRSTUVWXYZ",
        "!@#$%^&*()-+" };
    bool contains[] = { false, false, false, false };
    int ret = 0;

    for (int i = 0; i < 4; i++)
    {
        for (int j = 0; j < constraints[i].size(); j++)
        {
            if (s.find(constraints[i][j]) != -1)
            {
                contains[i] = true;
            }
        }
        if (!contains[i])
        {
            ret++;
            n++;
        }
    }

    if (n < 6)
    {
        ret += 6 - n;
    }
    cout << ret;
    return 0;
}