#include <bits/stdc++.h>
using namespace std;
#define M 100

int main() {
     
    int l;
    cin>>l;
    char arr[l+1];
    for(int i=0;i<l;i++)
    {
    	cin>>arr[i];
    }
    int ans=0;
    int count1=0,count2=0,count3=0,count4=0;
    for(int i=0;i<l;i++)
    {
        if(arr[i]=='0' || arr[i]=='1' || arr[i]=='2' || arr[i]=='3' || arr[i]=='4' || arr[i]=='5' || arr[i]=='6' || arr[i]=='7' || arr[i]=='8' || arr[i]=='9')
        {
            count1+=1;
            continue;
        }
        if(arr[i]=='a' || arr[i]=='b' || arr[i]=='c' || arr[i]=='d' || arr[i]=='e' || arr[i]=='f' || arr[i]=='g' || arr[i]=='h' || arr[i]=='i' || arr[i]=='j' || arr[i]=='k' || arr[i]=='l' || arr[i]=='m' || arr[i]=='n' || arr[i]=='o' || arr[i]=='p' || arr[i]=='q' || arr[i]=='r' || arr[i]=='s' || arr[i]=='t' || arr[i]=='u' || arr[i]=='v' || arr[i]=='w' || arr[i]=='x' || arr[i]=='y' || arr[i]=='z')
        {
            count2+=1;
            continue;
        }
        
        if(arr[i]=='A' || arr[i]=='B' || arr[i]=='C' || arr[i]=='D' || arr[i]=='E' || arr[i]=='F' || arr[i]=='G' || arr[i]=='H' || arr[i]=='I' || arr[i]=='J' || arr[i]=='K' || arr[i]=='L' || arr[i]=='M' || arr[i]=='N' || arr[i]=='O' || arr[i]=='P' || arr[i]=='Q' || arr[i]=='R' || arr[i]=='S' || arr[i]=='T' || arr[i]=='U' || arr[i]=='V' || arr[i]=='W' || arr[i]=='X' || arr[i]=='Y' || arr[i]=='Z')
        {
            count3+=1;
            continue;
        }
        if(arr[i]=='!' || arr[i]=='@' || arr[i]=='#' || arr[i]=='$' || arr[i]=='%' || arr[i]=='^' || arr[i]=='&' || arr[i]=='*' || arr[i]=='(' || arr[i]==')' || arr[i]=='-' || arr[i]=='+')
        {
            count4+=1;
        }
    }
    //ut<<count1<<" "<<count2<<" "<<" "<<count3<<" "<<count4<<endl;
    if(l>=6)
    {
        if(count1<1)
        {
            ans+=1;
        }
        if(count2<1)
        {
            ans+=1;
        }
        if(count3<1)
        {
            ans+=1;
        }
        if(count4<1)
        {
            ans+=1;
        }
        cout<<ans<<endl;
    }
    else 
    {
        if(count1<1)
        {
            ans+=1;
        }
        if(count2<1)
        {
            ans+=1;
        }
        if(count3<1)
        {
            ans+=1;
        }
        if(count4<1)
        {
            ans+=1;
        }
        if(ans+count1+count2+count3+count4<6)
        {
        	int res=6-(ans+count1+count2+count3+count4);
        	cout<<ans+res<<endl;
        }
        else
        {
        	cout<<ans<<endl;
        }
    }
    return 0;
}