题解 | #字符个数统计#

import java.util.; import java.io.; public class Main{ public static void main(String[] args)throws IOException{ BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); String str = null; while((str = in.readLine())!= null){ Set set = new HashSet<>(); int sum = 0; int len = str.length(); for(int i = 0;i <= len-1;i++){ if(!set.contains(str.charAt(i))){ sum ++; set.add(str.charAt(i)); } } System.out.println(sum); }

}

}