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


int main() {
    int n;
    cin>>n;
    string str;
    cin>>str;
    int ans;
    int d=0,l=0,u=0,s=0;
    for(int i=0;i<n;++i){
        if(isdigit(str[i]))
            ++d;
        else if(islower(str[i]))
            ++l;
        else if(isupper(str[i]))
            ++u;
        else
            ++s;
    }
    ans=1-min(1,d)+1-min(1,l)+1-min(1,u)+1-min(1,s);
    if(n+ans<6)
        ans+=6-(n+ans);
    cout<<ans;
    return 0;
}