题解 | #字符个数统计#

import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner sc=new Scanner(System.in);
        String s=sc.nextLine().replace(" ","");
        HashSet<Character>  hs=new HashSet<Character>();
        for(int i=0;i<s.length();i++){
            Character c=s.charAt(i);
            int ascll=Integer.valueOf(c);
           if(ascll>=0&&ascii<=127){
             hs.add(c);

           }
        }
        System.out.println(hs.size());
    }
}