#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <bits/stdc++.h>
using namespace std;

using namespace std;
int main() {
    int n;
    int cap=0,sm=0,nm=0,sp=0;
    cin>>n;
    string s;
    cin>>s;
    for(int i=0;i<n;i++)
    {
        if(s[i]>='A'&&s[i]<='Z')
            cap=1;
       else if(s[i]>='a'&&s[i]<='z')
            sm=1;
        else if(isdigit(s[i]))
            nm=1;
       else 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]=='+')
           sp=1;
    }
    int nreq=4-(cap+sm+nm+sp);
    int p=n+nreq;
    if(p<6)
        cout<<nreq+6-p<<"\n";
    else
        cout<<nreq<<"\n";
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    return 0;
}