#include<bits/stdc++.h>
using namespace std;
#define MOD 1000000007
#define pb push_back
#define X first
#define Y second
typedef long long ll;
typedef pair<ll,ll> p;
#define vi vector<ll>
#define mem(x,y) memset(x,y,sizeof(x))
bool fun(char ch,string s)
{
    for(int i=0;i<s.size();i++)
    {
        if(s[i]==ch)
            return 1;
    }
    return 0;
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    //freopen ("input.txt","r",stdin);
    //freopen ("output.txt","w",stdout);
    ll t,i,j;
    string numbers = "0123456789";
    string lower_case = "abcdefghijklmnopqrstuvwxyz";
    string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    string special_characters = "!@#$%^&*()-+";
    int n;
    cin>>n;
    string s;
    cin>>s;
    bool dig=0,lc=0,uc=0,sc=0;
    for(i=0;i<n;i++)
    {
        if(fun(s[i],numbers))
            dig=1;
        if(fun(s[i],lower_case))
            lc=1;
        if(fun(s[i],upper_case))
            uc=1;
        if(fun(s[i],special_characters))
            sc=1;
    }
    int ans=0;
    if(!dig)
        ans++;
    if(!sc)
        ans++;
    if(!lc)
        ans++;
    if(!uc)
        ans++;
    if(ans+n<6)
        ans+=6-(ans+n);
    cout<<ans;
}