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

int main(){
	
	int n,t,k,m,ans=0;
	cin>>n;
	string str;
	cin>>str;
 k=str.length();
 string chk = "!@#$%^&*()-+";
 int c1=0,c2=0,c3=0,c4=0,c5=0;
 for(int i=0;i<n;i++)
 {
 	if(str[i]>=97 && str[i]<=122)
 	c1=1;
 	else if(str[i]>=65 && str[i]<=90)
 	c2=1;
 	else if(str[i]>=48 && str[i]<=57)
 	c3=1;
 	else{
 		for(int j=0;j<chk.size();j++)
 		{
 			if(chk[j]==str[i])
 			{
 				c4=1;
 				break;
			 }
		 }
	 }
 }
if(c1==0)
ans++;
if(c2==0)
ans++;
if(c3==0)
ans++;
if(c4==0)
ans++;
if(n>=6)
cout<<ans;
else
{
	if(n+ans<6)
	cout<<ans+(6-(n+ans));
	else
	cout<<ans;
}
}