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

#define fast ios_base::sync_with_stdio(false);cin.tie(0)
#define pb push_back
#define mp make_pair
#define ft first
#define sd second
#define snd sd.ft
#define td sd.sd
#define debug(x) cout<<"### x is: "<<x<<"###"<<endl
#define all(a) a.begin(),a.end()
#define tc int t;scanf("%d",&t);while (t-->0)

#define ninf -1000000000
#define pinf 1000000000

typedef long long ll;
const ll MOD= 1e9+7;
typedef vector<pair<ll,ll> > vecpair;
typedef vector<pair<ll, pair<ll,ll> > > vecpair3;

ll power(ll a, ll b) {ll ret=1;while(b) {if(b&1) ret*=a;a*=a;if(ret>=MOD) ret%=MOD;if(a>=MOD) a%=MOD;b>>=1;}return ret;}
ll invmod(ll x) {return power(x,MOD-2);}

string numbers = "0123456789";
string lower_case = "abcdefghijklmnopqrstuvwxyz";
string upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
string special_characters = "!@#$%^&*()-+";

bool nn,lc,uu,ss;

int main()
{

    //freopen("TASK.in","r",stdin);freopen("TASK.out","w",stdout);
	ll n,i,j;
	
	cin>>n;
	string s;
	cin>>s;
	
	for(i=0;i<(ll)s.size();i++)
	{
		for(j=0;j<(ll)numbers.size();j++)
		if(s[i] == numbers[j]) nn=1;
		
		for(j=0;j<(ll)lower_case.size();j++)
		if(s[i] == lower_case[j]) lc=1;
		
		for(j=0;j<(ll)upper_case.size();j++)
		if(s[i] == upper_case[j]) uu=1;
		
		for(j=0;j<(ll)special_characters.size();j++)
		if(s[i] == special_characters[j]) ss=1;
	}
	
	ll ans= nn+lc+uu+ss;
	//debug(ans);
	
	if(s.size()<6)
	{
		ll sz= s.size()+ 4 -ans;
		//debug(ans);
		if(sz>=6)
		cout<<4-ans;
		else
		cout<<4-ans+ 6-sz;
	}
	else
	{
		cout<<4-ans;
	}
	return 0;
}