#include <bits/stdc++.h>
using namespace std;
int main(){
	long long a[100],t=0,s=0,d=0,f=0,p=0,i,l;
	string b[1000],n,numbers,lower_case,upper_case,special_characters;
	numbers = "0123456789";
	lower_case = "abcdefghijklmnopqrstuvwxyz";
	upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
	special_characters = "!@#$%^&*()-+";
	cin>>l>>n;
	for(i=0;i<n.size();i++){
		if(numbers.find(n[i])==-1)s++;
		if(lower_case.find(n[i])==-1)t++;
		if(upper_case.find(n[i])==-1) d++;
		if(special_characters.find(n[i])==-1)f++;
	}
	if(s==n.size()) p++;
	if(t==n.size()) p++;
	if(d==n.size()) p++;
	if(f==n.size()) p++;
	cout<<max(p,6-l);
}