#include<bits/stdc++.h>
using namespace std;
#include<stdio.h>
#include<math.h>
#define pb push_back
#define mp make_pair
#define endl '\n'
#define lli long long int
#define li long int 
long int mod=1e9+7;
string ch;
li i,j,ans,n,big,sp,sm,q;
int h;
int main()
{
   /* #ifndef ONLINE_JUDGE
    freopen("input.txt","r",stdin);
    freopen("output.txt","w",stdout);
    #endif  */
    ios::sync_with_stdio(0);
    cin.tie(0);
    cin>>n;
    cin>>ch;
    for(i=0 ; i<n ; i++)
    {
        h=(int)ch[i];
        if(h>=65 && h<=90)
         big++;
         else if(h>=97 && h<=122)
         sm++;
         else if(h>=33 && h<=45)
         sp++;
        else if(h>=48 && h<=57)
         q++;
    }
        if(sm==0)
        ans++;
        if(big==0)
        ans++;
        if(sp==0)
        ans++;
    if(q==0)
        ans++;
    if((n+ans)<6)
    cout<<6-n;
    else
    cout<<ans;
    return 0;   
}