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


int main() {
    int t,i,l,u,d,sp;
    char s[110];
    cin>>t;
    cin>>s;
    l=u=d=sp=0;
    for(i=0;i<t;i++)
    {
        if(s[i]>='a' && s[i]<='z')
            l=1;
        else if(s[i]>='A' && s[i]<='Z')
            u=1;
        else if(s[i]>='0' && s[i]<='9')
            d=1;
        else
            sp=1;
    }
    int x=0;
    if(l==0)
        x++;
    if(u==0)
        x++;
    if(d==0)
        x++;
    if(sp==0)
        x++;
    
    if(6-t>x)
        x=6-t;
    
    cout<<x;
    return 0;
}