#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* pass) {
    // Return the minimum number of characters to make the password strong
    char a[100] = "!@#$%^&*()-+";
    char b[100] = "0123456789";
    char c[100] = "abcdefghijklmnopqrstuvwxyz";
    char d[100] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        int c1= 0,i, j, c2 = 0, c3 = 0, c4 = 0;
    for(i = 0; i < n; i++)
    {
        for(j = 0; j < 12; j++)
        {
            if(pass[i] == a[j])
            {
                c1 = 1;
            }
        }
        for(j = 0; j < 26; j++)
        {
            if(pass[i] == c[j])
            {
                c2 = 1;
            }
        }
        for(j = 0; j < 12; j++)
        {
            if(pass[i] == d[j])
            {
                c3 = 1;
            }
        }
        for(j = 0; j < 10; j++)
        {
            if(pass[i] == b[j])
            {
                c4 = 1;
            }
        }
    }
    int count = 0;
    int x = 6;
    if(c1 != 1)
        count++;
     if(c2 != 1)
        count++;
    if(c3 != 1)
        count++;
    if(c4 != 1)
        count++;
    int len = strlen(pass);
  //  int len1 = x - len;
    len = len + count;
    if(len >= 6)
        return count;
   // printf("%d", len1);
    if(len < 6)
    {
        return  x - len + count; 
    }
       return count; 
}

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