#include<bits/stdc++.h>
using namespace std;
int main()
{
  int n,count=1,count1=1,count2=1,count3=1; cin>>n;
  string s; cin>>s;
  string a="0123456789";
  string b="!@#$%^&*()-+";
    
    for(int i=0;i<n;i++)
    {
        if(s[i]>=65&&s[i]<=90&&count==1)
            count--;
        else if(s[i]>=97&&s[i]<=122&&count1==1)
            count1--;
        else if(s[i]>=48&&s[i]<=57&&count2==1)
              count2--;
        else {
            for(int j=0;j<b.length();j++)
               {
                if(s[i]==b[j]&&count3==1)
                    count3--;}

        }


    }
 //  cout<<count<<count1<<count2<<count3;
    if(n>=6)
        cout<<count+count1+count2+count3;
    else
        cout<<max(count+count1+count2+count3,6-n);
return 0;}