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

bool isPresent(char* string, int n)
{
    char* spl = "!@#$%^&*()-+";
    int i,j;
    for(i=0;i<n;i++)
    {
        for(j=0;j<12;j++)
        {
            if(string[i] == spl[j])
                return true;
        }
    }
    return false;
}

int minimumNumber(int n, char* password) {
    // Return the minimum number of characters to make the password strong
    bool number = false;
    bool lower = false;
    bool upper = false;
    bool spl = false;
    int i,answer=0;
    for(i=0;i<n;i++)
    {
        if(password[i] >= '0' && password[i] <= '9')
            number = true;
        else if(password[i]>='a' && password[i]<='z')
            lower = true;
        else if(password[i]>='A' && password[i]<='Z')
            upper = true;                        
    }
    spl = isPresent(password, n);
    if(!number)
        answer++;
    if(!lower)
        answer++;
    if(!upper)
        answer++;
    if(!spl)
        answer++;
    
    return (n+answer<6)?6-n:answer;
}

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;
}