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

int main() {
    int ll;
    char a[100];
    cin>>ll>>a;
    int j=0,u=0,l=0,s=0,n=0;
    for(int i=0;i<ll;i++)
    {
        if(a[i]>=48 && a[i]<=57)
            n++;
        else if(a[i]>=65 && a[i]<=90)
            u++;
        else if(a[i]>=97 && a[i]<=122)
            l++;
        else if(a[i]==33 || a[i]==64 || a[i]==35 || a[i]==36 || a[i]==37 || a[i]==94 || a[i]==38 || a[i]==42 || a[i]==40 || a[i]==41 || a[i]==45 || a[i]==43)
            s++;
    }
    if(u==0)
        j++;
    if(l==0)
        j++;
    if(s==0)
        j++;
    if(n==0)
        j++;
    if(ll<6){
        int v=6-ll;
        if(v>j)
            cout<<6-ll<<endl;
        else
            cout<<j<<endl;
    }
    else 
        cout<<j<<endl;
    return 0;
}