#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    
    string s; int n;
    cin>>n;
    cin>>s;
    
    int arr[5] = {0};
    
    if(n>5) arr[0]=1;
    
    for(int i=0; i<n; i++){
        
        char c=s[i];
        if(c>=48 && c<=57) arr[1]=1;
        if(c>=65 && c<=90) arr[2]=1;
        if(c>=97 && c<=122) arr[3]=1;
        if((c==33)||(c>=35 && c<=38)||(c==94)||(c==64)||(c==45)||(c>=40 && c<=43)) arr[4]=1;
    }
    
    int count=0;
    
    for(int i=1; i<5; i++){
        
        if(arr[i]==0) count++;
    }
    
    //cout<<"--"<<count<<endl;
    
    if(arr[0]!=1){
        
        int diff = 6-n;
        //cout<<"diff "<<diff<<endl;
        if(count<diff){
            count = diff;
        }
    }
    
    cout<<count<<endl;
    
    
    return 0;
}