#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <bits/stdc++.h>
using namespace std;


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */
    int n;
    cin>>n;
    int lo=0,hi=0,dig=0,spec=0,ans=0;
    for(int i=0;i<n;i++)
    {
        char c;
        cin>>c;
        if(islower(c))
        {
            lo=1;
        }
        else if(isupper(c))
        {
            hi=1;
        }
        else if(isdigit(c))
        {
            dig=1;
        }
        else if(c=='!' || c=='@' || c=='#' || c=='$' || c=='%' || c=='^' || c=='&' || c=='*' || c=='(' || c==')' || c=='-' || c=='+')
            spec=1;
    }
    ans=4-lo-hi-dig-spec;
    if(ans+n<6)
        ans+=6-(n+ans);
    cout<<ans;
    return 0;
}