//coded by dsingh_24
#include<bits/stdc++.h>
#define ll          long long
#define pb          push_back
#define mp          make_pair
#define pll         pair<long long,long long>
#define vll          vector<long long>
#define all(a)      (a).begin(),(a).end()
#define F           first
#define S           second
#define sz(x)       (long long)x.size()
#define hell        1000000007
#define lbnd        lower_bound
#define ubnd        upper_bound
#define bs          binary_search
#define ios         ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
using namespace std;
int main()
{
	ios
	
    string s;
    ll i,j,c=0,f=0,n,f1=0,f2=0,f3=0;
    cin>>n>>s;
    for(i=0;i<s.size();i++)
    {
    	if(s[i]>='a'&&s[i]<='z'&&f1==0)c++,f1=1;
    	if(s[i]>='A'&&s[i]<='Z'&&f2==0)c++,f2=1;
    	if(s[i]>='0'&&s[i]<='9'&&f3==0)c++,f3=1;
    	string a="!@#$%^&*()-+";
    	if(f==0)
    	{
    		for(j=0;j<a.size();j++)
        	if(a[j]==s[i])f=1;
        	if(f)c++;
		}
	}
	if(n<6)cout<<max(6-n,4-c);else
	cout<<max(0LL,4-c);
	return 0;
}