#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 i=0;
   int count1=1,count2=1,count3=1,count4=1;
    while(password[i]!='\0')
    {
        if(password[i]>=48&&password[i]<=57)
            count1=0;
        else if(password[i]>=97&&password[i]<=122)
            count2=0;
        else if(password[i]>=65&&password[i]<=90)
            count3=0;
        else
            count4=0;
        i++;
    }
    if(strlen(password)>=6)
    {
        printf("%d",count1+count2+count3+count4);
    }
    else
    {
        if(strlen(password)+count1+count2+count3+count4>=6)
            printf("%d",count1+count2+count3+count4);
        else
            printf("%d",6-(count1+count2+count3+count4+strlen(password))+(count1+count2+count3+count4));
    }
    return 0;
}