#include<set>
#include<map>
#include<queue>
#include<stack>
#include<vector>
#include<string>
#include<math.h>
#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<iostream>
#include<algorithm>
#define mp make_pair
#define fi first
#define se second
using namespace std;
typedef long long ll;
typedef pair<ll,ll> pll;
typedef pair<int,int> pii;
const int MAXN= (int)1e5+10;
const int MOD = (int)1e9+7;
char hhh[]={"!@#$%^&*()-+"};
char str[MAXN];
int main()
{
	int n;	
	cin>>n;	
	scanf("%s",str+1);
	int flag=0;
	for(int i=1;i<=n;i++){
		if(str[i]>='0'&&str[i]<='9')flag|=1;
		else if(str[i]>='a'&&str[i]<='z')flag|=2;
		else if(str[i]>='A'&&str[i]<='Z')flag|=4;
		else {
			for(int j=0;hhh[j]!='\0';j++)if(str[i]==hhh[j])flag|=8;
		}
	}
	int num=0;
	while(flag){
		num+=(flag&1);
		flag>>=1;
	}
	
	num=4-num;
	int ans=num+max(0,6-n-num);
	cout<<ans<<endl;
	return 0;
}