#include <iostream>
#include <math.h>
#include <bitset>
#include <stdio.h>
#include <algorithm>
#include <string.h>
#include <ctime>
#include<unordered_map>
//#include <bits/stdc++.h>
using namespace std;

#define f(i,n)  for(int i=0;i<n;++i)
#define fab(i,a,b)	for(int i=a;i<=b;++i)
#define finc(i,a,b,in)	for(int i=a;i<=b;i+=in)
#define ll  long long
#define li long
#define sf(x)   scanf("%d",&x);
#define sfc(x)   scanf("%c",&x);
#define sfl(x)   scanf("%ld",&x);
#define sfll(x)   scanf("%lld",&x);

#define pf(x)   printf("%d",(int)x);
#define pfl(x)   printf("%ld",(long)x);
#define pfll(x)   printf("%lld",(long long)x);
#define pfs(x)   printf(x);
#define pfnl	printf("\n");
#define pii	pair<int,int>
#define ms(a,val,size)	memset(a,val,size*sizeof(typeof(*a)))
#define Mod (ll)(1e9+7)
#define INF 0x3f3f3f3f
#define pb push_back
#define MKSTR( x ) #x

#define seti(x) __builtin_popcount(x)	//No of Bits Set
#define setli(x) __builtin_popcountl(x)
#define setll(x) __builtin_popcountll(x)
#define numOfTrailingZeros(x)	__builtin_ctz(x)
#define numOfLeadingZeros(x)	__builtin_clz(x)
#define LSSetBit(x)	 __builtin_ffs(x)	//Returns position of least significant Set Bit in x eg 1 for 1
#define powi(x,y)	__builtin_powi(x,y)	//double,int : faster than pow; powif,powil
#define toBinary(x,noOfBits)	std::bitset<noOfBits>(x)
#define ispow2(x)	((x&(x-1)) == 0)	//Fails just for x==0
//#define ispow2(x)	(x && !(x & (x - 1)))
#define modIfPow2(n,d) (n&(d-1))	//	n%d  if ispow2(d)==1
#define fastIO 	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);

//#define DEBUG

#ifdef DEBUG
	//	debug here	;	use cerr
#endif

ll modPow(ll n, ll exp)
{
	if(exp==0)	return 1;
	if(exp==1 || n==0 || n==1 )	return n%Mod;
	if(exp%2){
		ll ans=modPow(n,(exp-1)/2);
		return ((ans*ans)%Mod * (n%Mod))%Mod;
	}
	else{
		ll ans=modPow(n,exp/2);
		return (ans*ans)%Mod;
	}
}


int main()
{
	fastIO

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

//	unordered_map<char,bool>m;
//	f(i,numbers.size())	m[numbers[i]]=1;
//	f(i,lower_case.size())	m[lower_case[i]]=1;
//	f(i,upper_case.size())	m[upper_case[i]]=1;
//	f(i,special_characters.size())	m[special_characters[i]]=1;

	int n;
	cin>>n;
	string s;
	cin>>s;
	bool num=0,low=0,up=0,spe=0;
	f(i,s.size()){
		if(numbers.find(s[i])!=std::string::npos) num=1;
		else if(lower_case.find(s[i])!=std::string::npos) low=1;
		else if(upper_case.find(s[i])!=std::string::npos) up=1;
		else if(special_characters.find(s[i])!=std::string::npos) spe=1;
	}
    //cout<<num<<" "<<low<<" "<<up<<" "<<spe<<"\n";
	int all=num+low+up+spe;
    //cout<<all;
	if(all==4){
		if(s.size()>=6)	cout<<0;
		else	cout<<6-s.size();
	}
	else{
		int ans=4-all;
        cout<<ans+max(0,6-((int)(s.size())+ans));
//		if(s.size()+ans>=6)	cout<<ans;
//		else	cout<<6-s.size()+ans;
	}


	return 0;
}