#include <bits/stdc++.h>
#define ll long long int
using namespace std;

int main()
{
ll n;
cin>>n;
    string s;
    cin>>s;
    set<char>s1;
    s1.insert('!');
    s1.insert('@');
    s1.insert('#');
    s1.insert('$');
    s1.insert('%');
    s1.insert('^');
    s1.insert('&');
    s1.insert('*');
    s1.insert('(');
    s1.insert(')');
    s1.insert('-');
    s1.insert('+');

    ll c1=0,c2=0,c3=0,c4=0;
    for(ll i=0;i<n;i++)
    {
        if(isalpha(s[i])&&isupper(s[i]))
            c1++;
            else
        if(isalpha(s[i])&&islower(s[i]))
            c2++;
            else
            if(isdigit(s[i]))
            c3++;
            else
            if(s1.find(s[i])!=s1.end())
                c4++;
    }
    ll count=0;
    if(c1==0)
        count++;
    if(c2==0)
        count++;
        if(c3==0)
        count++;
        if(c4==0)
        count++;
    if(n<6)
        count=max(count,(6-n));
       cout<<count<<endl;
    return 0;
}