#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* password = (char *)malloc(512000 * sizeof(char));
    scanf("%s", password);
    int ans=0;
    int a[4]={0};
    for(int i=0;i<n;i++){
        if(password[i]>='A'&&password[i]<='Z'){
            a[0]++;
        }
        else if(password[i]>='a'&&password[i]<='z'){
            a[1]++;
        }
        else if(password[i]>='0'&&password[i]<='9'){
            a[2]++;
        }
        else if(password[i]=='!' || password[i]=='@' || password[i]=='#' || password[i]=='$' || password[i]=='%' || password[i]=='^' || password[i]=='&' || password[i]=='*' || password[i]=='(' || password[i]==')' || password[i]=='-' || password[i]=='+'){
            a[3]++;
        }
    }
    for(int i=0;i<4;i++){
        if(a[i]==0){
            n++;
            ans++;
        }
    }
    if(n<6)
    ans+=(6-n);
    printf("%d",ans);
    return 0;
}