#include<bits/stdc++.h>
using namespace std;
int main()
{
    int num;
    cin>>num;
    string numbers,lower_case,upper_case,special_characters,str;
    bool b=0;
    int n=0,l=0,u=0,s=0;
    cin>>str;
    numbers = "0123456789";
    lower_case = "abcdefghijklmnopqrstuvwxyz";
    upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    special_characters = "!@#$%^&*()-+";
    for(int i=0;i<str.length();i++)
    {
        if(numbers.find(str[i]) != string::npos)
        {
            n=1;
        }
        else if(lower_case.find(str[i]) != string::npos)
        {
            l=1;
        }
        else if(upper_case.find(str[i]) != string::npos)
        {
            u=1;
        }
        else if(special_characters.find(str[i])!=string::npos)
        {
            s=1;
        }
        if(n&&l&&u&&s)
        {
            break;
        }
    }
    if(!b)
    {
        int ans = !n + !l + !u + !s;
        if(ans + str.length() < 6)
        {
            ans = 6 - str.length();
        }
        cout<<ans<<endl;
    }
    return 0;
}