#include <bits/stdc++.h>

using namespace std;


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    
    
    string s1 = "0123456789";
    string s2 = "abcdefghijklmnopqrstuvwxyz";
    string s3 = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    string s4 = "!@#$%^&*()-+";
    
    bool f1, f2, f3, f4, f5;
    f1 = f2 = f3 = f4 = f5 = false;
    
    int n;
    cin>>n;
    char ch[n];
    
    for(int i=0; i<n; i++)
        cin>>ch[i];
    
    
    for(int i=0; i<n; i++)
    {
        if(s1.find(ch[i]) != string::npos)
            f1 = true;
        else if(s2.find(ch[i]) != string::npos)
            f2 = true;
        else if(s3.find(ch[i]) != string::npos)
            f3 = true;
        else if(s4.find(ch[i]) != string::npos)
            f4 = true;
    }
    
    
    int ctr = 0;
        if(f1)
            ctr++;
        if(f2)
            ctr++;
        if(f3)
            ctr++;
        if(f4)
             ctr++;
          
        if(ctr >=4 && n >= 6)
            cout<<"0";
    
        else if(n >= 6 && ctr < 4 )
            cout<<4-ctr;
    
        else if(ctr >=4 && n < 6)
            cout<<6-n;
        else
            (6-n > 4-ctr)?cout<<6-n:cout<<4-ctr;
        cout<<endl;
    
            
    
    return 0;
}