#include <bits/stdc++.h> // std::cout          // std::priority_queue
using namespace std;
int i,j,k,l,l1,l2,l3,l4,n;
char a[10001];
int main (){
   cin>>n;
//cout<<int('(');
    for(i=1; i<=n; i++)
    {cin>>a[i];
     if (a[i]>=97 && a[i]<=122) l1=1;
     if (a[i]>=65 && a[i]<=90) l2=1;
    if (a[i]>=48 && a[i]<=57) l3=1;
     if (a[i]=='!' || a[i]=='@' || a[i]=='#' || a[i]=='$' || a[i]=='%' || a[i]=='^' || a[i]=='&' || a[i]=='*' || a[i]=='(' || a[i]==')' || a[i]=='-' || a[i]=='+') l4=1;
   } 
    l=l1+l2+l3+l4;
    if (n>=6) cout<<4-l;
    else cout<<max(4-l,6-n);
return 0;
}