//vivekmufc
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> ii;

#define ff first
#define ss second 
#define INF                         (int)1e9
#define MOD                         (int)1e9+7
#define N                           500005

string sp = "!@#$%^&*()-+";

int main() {

    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n;
    string s;
    cin>>n>>s;
    int ans = 0;
    int m = sp.size();
    int flg1 = 0, flg2 = 0, flg3 = 0, flg4 = 0;
    for (int i = 0; i < n; ++i)
    {
    	if(s[i] >= '0' && s[i] <= '9')
    		flg1 = 1;
    	if(s[i] >= 'A' && s[i] <= 'Z')
    		flg2 = 1;
	    if(s[i] >= 'a' && s[i] <= 'z')
			flg3 = 1;
		for (int j = 0; j < m; ++j)
		{
			if(s[i] == sp[j])
				flg4 = 1;
		}
    }
    if(!flg1)
    	ans++;
    if(!flg2)
    	ans++;
    if(!flg3)
    	ans++;
    if(!flg4)
    	ans++;
    // cout<<ans<<endl;
    if(ans+n < 6)
    	ans += 6 - ans-n;
    cout<<ans;
}