#include <iostream>
using namespace std;

int main()
{
    int n;
    cin>>n;
    
    char s[n];
    for(int i=0; i<n; i++)
        cin>>s[i];
    
    int l=1, u=1, c=1, d=1;
    for(int i=0; i<n; i++) {
        if('a'<=s[i] && s[i]<='z')
            l=0;
        else if('A'<=s[i] && s[i]<='Z')
            u=0;
        else if('0'<=s[i] && s[i]<='9')
            d=0;
        else
            c=0;
    }
    
    int total = u+l+d+c;
    if(n>6)
        cout<<total<<endl;
    else
        if(total > 6-n)
            cout<<total<<endl;
        else
            cout<<(6-n)<<endl;
    
    return 0;
}