#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) {
    // Return the minimum number of characters to make the password strong
    bool one = 1,two = 1,thre = 1,four = 1,five = 1;
    int i;
    for(i = 0; i< n; i++){
        
        if(password[i] >= 'a' && password[i] <= 'z')
            thre = 0;
        if(password[i] <= 'Z' && password[i] >= 'A')
            four = 0;
        if(password[i] <= '9' && password[i] >= '0')
            two = 0;
        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] == '=' )
           five = 0;
            
    }
    int var = two + thre + four + five;
    if(var + n < 6)
        return 6 - n;
    else
        return var;
}

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;
}