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

int isSpecial(char a) {
    char sp[15] = "!@#$%^&*()-+";
    char *ptr = sp;
    while(*ptr) {
        if(*ptr==a)
            return 1;
        ptr++;
    }
    return 0;
}

int minimumNumber(int n, char* password) {
    // Return the minimum number of characters to make the password strong
    int num = 0;
    int lower = 0;
    int upper = 0;
    int special = 0;
    int len = strlen(password);
    char *ptr;
    ptr = password;
    while(*ptr) {
        if(*ptr>='0' && *ptr<='9') {
            num = 1;
        } else if(*ptr>='a' && *ptr<='z') {
            lower = 1;
        } else if(*ptr>='A' && *ptr<='Z') {
            upper = 1;
        } else if(isSpecial(*ptr)==1) {
            special = 1;
        }
        ptr++;
    }
    int count = 0;
    if(num==0)  count++;
    if(lower==0)  count++;
    if(upper==0)  count++;
    if(special==0)  count++;
    if(len<6) {
        if(count<6-len)
            count = 6-len;
    }
    return count;
}

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;
}