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


int main() {
    int n;
    cin>>n;
    string s;
    cin>>s;
    int val=6-s.length();
    bool f1=0,fa=0,fA=0,fs=0;
    for(int i=0;i<s.length();i++){
        if(s[i]-48>=0 && s[i]-48<=9)f1=1;
        if(s[i]-65>=0 && s[i]-65<=25)fa=1;
        if(s[i]-97>=0 && s[i]-97<=25)fA=1;
        if(s[i]=='!' || s[i]=='@' || s[i]=='#' || s[i]=='$' || s[i]=='%' || s[i]=='^' || s[i]=='&' || s[i]=='*' || s[i]=='('|| s[i]==')'|| s[i]=='-' || s[i]=='+' )fs=1;
        
    }
    int ans=0;
    if(f1==0)ans++;
    if(fa==0)ans++;
    if(fA==0)ans++;
    if(fs==0)ans++;
    ans=max(ans,val);
    cout<<ans<<endl;
    
    return 0;
}