#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* p) {
    // Return the minimum number of characters to make the password strong
    int l,c1=0,c2=0,c3=0,c4=0;
    l=strlen(p);
    int i;
    for(i=0;i<l;i++)
    {
        if((p[i]>=48 && p[i]<=57))
        {
            c1++;
        }
        else if((p[i]>=97 && p[i]<=122))
        {
            c2++;
        }
        else if((p[i]>=65 && p[i]<=90))
        {
            c3++;
        }
        else
        {
            if(p[i]=='!' || p[i]=='@' || p[i]=='#' ||  p[i]=='%' || p[i]=='$' || p[i]=='^' || p[i]=='&' || p[i]=='*' || p[i]=='(' || p[i]==')' || p[i]=='-' || p[i]=='+')
            {
                c4++;
            }
        }
    }
    int r=0;
    if(c1==0)
    {
        r++;
    }
    if(c2==0)
    {
        r++;
    }
    if(c3==0)
    {
        r++;
     
    }
    if(c4==0)
    {
        r++;
    }
    if((r+n)<6)
    {
        r=6-n;
    }
    return r;
}

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;
}