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

bool check(char c)
{
    string s="!@#$%^&*()-+";
    for(int i=0;i<s.size();i++)
        if(s[i]==c)
            return 1;
    return 0;
}
int main() {
    int n;
    cin>>n;
    char s[n];
    cin>>s;
    int a=0;
    int b=0;
    int c=0;
    int d=0;
    for(int i=0;i<n;i++)
    {
        if(s[i]>=48&&s[i]<=57)
            a=1;
        else if(s[i]>=65&&s[i]<=90)
            b=1;
        else if(s[i]>=97&&s[i]<=122)
            c=1;
        else if(check(s[i])==1)
            d=1;
    }
    int sum=a+b+c+d;
     int total=0;
    if(sum!=4)
        total+=4-sum;
    if(n<6)
        total=max(total,6-n);
    cout<<total<<endl;
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    return 0;
}