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

int main()
{
    int n;
    cin >> n;

    bool digit = false;
    bool lw = false;
    bool up = false;
    bool sp = false;
    string spec = "!@#$%^&*()-+";
    string s;
    cin >> s;
    for(int i = 0; i < s.length(); i++)
    {
        if(s[i] >= '0' && s[i] <= '9')
            digit = true;
        if(s[i] >= 'a' && s[i] <= 'z')
            lw = true;
        if(s[i] >= 'A' && s[i] <= 'Z')
            up = true;
        for(int j = 0; j < spec.length(); j++)
            if(s[i] == spec[j])
                sp = true;
    }
    int need = 0;
    if(!digit) need++;
    if(!lw) need++;

    if(!up) need++;

    if(!sp) need++;
    cout << max(need, 6 - (int)s.length());
    return 0;
}