#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>



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