#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;

int is_small(char ch)
{
    if(ch>='a' && ch<='z')
        return 1;
    else return 0;
}
int is_big(char ch)
{
    if(ch>='A' && ch<='Z')
        return 1;
    else return 0;
}
int is_number(char ch)
{
    if(ch>='0' && ch<='9')
        return 1;
    else return 0;
}
int is_spec(char ch)
{
    if(ch=='!'||ch=='@'||ch=='#' || ch=='$'|| ch=='%' || ch=='^' || ch == '&' || ch=='*' || ch=='(' || ch==')' || ch=='-' || ch=='+')
        return 1;
    else return 0;
}
int main() {
    string s;
    int n,i;
    cin>>n;
    cin>>s;
    int flag1=0,flag2=0,flag3=0,flag4=0;
    for(i=0;i<n;i++)
    {
        if(is_spec(s[i]))
            flag1++;
        else if(is_number(s[i]))
            flag2++;
         else if(is_small(s[i]))
            flag3++;
         else if(is_big(s[i]))
            flag4++;
        
    }
    
    int count =0;
    if(flag1==0)
    { count++; n++;}
    if(flag2==0)
       { count++; n++;}
    if(flag3==0)
        { count++; n++;}
    if(flag4==0)
        { count++; n++;}
    
    if(n<6)
        count+=6-n;
    
    cout<<count;
    return 0;
}