题解 | #字符个数统计#

遍历字符串，hashmap去重，输出map size

import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner input = new Scanner(System.in);
        String s = input.nextLine();
        Map<String,String> map = new HashMap<>();
        for(int i=0;i<s.length();i++){
            map.put(s.charAt(i)+"",s.charAt(i)+"");
        }
        System.out.println(map.size());
    }
}