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

int minimumNumber(int n, char* password) {
    char numbers[] = "0123456789",lower_case[] = "abcdefghijklmnopqrstuvwxyz",upper_case[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ",special_characters[] = "!@#$%^&*()-+";
    int num=0,up=0,low=0,special=0,count=0;
    for(int i=0;i<n;i++)
    {
        if(strchr(numbers,password[i]))
         {
            num++;
          }
        else if(strchr(lower_case,password[i]))
        {
            low++;
        }
        else if(strchr(upper_case,password[i]))
        {
            up++;
        }
        else if(strchr(special_characters,password[i]))
        {
            special++;
        }
        if(num >0 && up>0 && low>0 && special>0)
        {
            break;
        }
    }
    if(num==0)
        count++;
    if(up==0)
        count++;
    if(low==0)
        count++;
    if(special==0)
        count++;
    if(n>=6)
        return count;
    else
        return n+count<6?(6-n):count;
    // Return the minimum number of characters to make the password strong
}

int main() {
    int n; 
    scanf("%i", &n);
    char* password = (char *)malloc(512000 * sizeof(char));
    scanf("%s", password);
    int answer = minimumNumber(n, password);
    printf("%d\n", answer);
    return 0;
}