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


int main() {
    int n; 
    scanf("%d\n",&n);
    char a[n];
    for(int i=0;i<n;i++){
        scanf("%c",&a[i]);
    }
    if(n>6){
         int count1=0,count2=0,count3=0,count4=0;
        for(int i=0;i<n;i++){
            if((a[i]>=48)&&(a[i]<=57)){
                count1=1;
              }
            if((a[i]>=65)&&(a[i]<=90)){
                count2=1;
              }
            if((a[i]>=97)&&(a[i]<=122)){
                count3=1;
              }
            if((a[i]=='!')||(a[i]=='@')||(a[i]=='#')||(a[i]=='$')||(a[i]=='%')||(a[i]=='^')||(a[i]=='&')||(a[i]=='*')||(a[i]=='(')||(a[i]==')')||(a[i]=='-')||(a[i]=='+')){
                count4=1;
              }
                        
        }
    int k=count1+count2+count3+count4;
            printf("%d",(4-k));
    }
    if (n<=6){
         int count1=0,count2=0,count3=0,count4=0;
        for(int i=0;i<n;i++){
            if((a[i]>=48)&&(a[i]<=57)){
                count1=1;
              }
            if((a[i]>=65)&&(a[i]<=90)){
                count2=1;
              }
            if((a[i]>=97)&&(a[i]<=122)){
                count3=1;
              }
            if((a[i]=='!')||(a[i]=='@')||(a[i]=='#')||(a[i]=='$')||(a[i]=='%')||(a[i]=='^')||(a[i]=='&')||(a[i]=='*')||(a[i]=='(')||(a[i]==')')||(a[i]=='-')||(a[i]=='+')){
                count4=1;
              }
                        
        }
    int k=count1+count2+count3+count4;
        int m=4-k;
        if((n+m)>=6){
            printf("%d",m);
        }
        else if ((n+m)<6){
            printf("%d",(6-n));
        }
            
    }
   
    return 0;
}