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

int chk(int n)
{
    if (n>0)
           return 0;
    else
        return 1;
}

int main() {
 
    int n,i,j,k,l,m,p;
    string s;
    cin>>n;
    cin>>s;
    l=s.length();
    j=0;
    k=0;
    m=0;
    p=0;
    for (i=0; i<l; i++)
    {
        if (s[i]>='a'&&s[i]<='z')   j++;
        else if (s[i]>='A'&&s[i]<='Z') k++;
        else if (s[i]>='0'&&s[i]<='9') m++;
        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]=='+') p++;
    }
    
    if (j>0&&k>0&&m>0&&p>0)
    {
        if (l>=6)
                cout<<"0\n";
        else 
                cout<<6-l<<"\n";
    }
    else
    {
        int ans=6-l,a=0;
        if (j==0)
        {
            a++;
            ans--;
        }
        if (k==0) 
        {
            a++;
            ans--;
        }
        if (m==0)
        {
            a++;
            ans--;
        }
        if (p==0)
        {
            a++;
            ans--;
        }
        if (ans>0)
        {
            cout<<ans+a<<"\n";
        }
        else
        {
            cout<<a<<"\n";
        }
    }

    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    return 0;
}