#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define INF 1e9
#define mod 1000000007
#define task ""
#define abs(x) ((x)>=0?(x):-(x))
#define fi first
#define se second
typedef long long ll;
void read(ll &x)
{
	scanf("%lld",&x);
}
void read(ll &x, ll &y)
{
	scanf("%lld%lld",&x,&y);
}
void read(ll &x, ll &y, ll &z)
{
	scanf("%lld%lld%lld",&x,&y,&z);
}
void print(ll x)
{
	printf("%lld ",x);
}
void println(ll x)
{
	printf("%lld\n",x);
}
ll a,b,c,d,n;
string s,numbers = "0123456789",lower_case = "abcdefghijklmnopqrstuvwxyz",upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ",special_characters = "!@#$%^&*()-+";
int main()
{
	//freopen("c.cpp","r",stdin);

	cin>>n;
	cin>>s;
	for(ll i=0;i<s.size();i++)
	{
		for(char ch:numbers)
			if(ch==s[i])
				a=1;
		for(char ch:lower_case)
			if(ch==s[i])
				b=1;
		for(char ch:upper_case)
			if(ch==s[i])
				c=1;
		for(char ch:special_characters)
			if(ch==s[i])
				d=1;
	}
	cout<<4-a-b-c-d+max(0LL,6-n-4+a+b+c+d);
}