#include <bits/stdc++.h>

using namespace std;

int main(){
	int n;
	cin >> n;
	string s;
	cin >> s;
	int cnt1 = 0,cnt2 = 0,cnt3 = 0,cnt4 = 0;
	for(int i = 0;i<n;i++){
		if(s[i]>='a'&&s[i]<='z')cnt1++;
		else if(s[i]>='A'&&s[i]<='Z')cnt2++;
		else if(s[i]>='0'&&s[i]<='9')cnt3++;
		else cnt4++;
	}
	int ans = 0;
	if(cnt1==0){
		ans++;
		n++;
	}
	if(cnt2==0){
		ans++;
		n++;
	}
	if(cnt3==0){
		ans++;
		n++;
	}
	if(cnt4==0){
		ans++;	
		n++;
	}
	if(n<=6)ans += 6-n;
	cout << ans << endl;
	return 0;
}