题解 | #字符个数统计#
字符个数统计
https://www.nowcoder.com/practice/eb94f6a5b2ba49c6ac72d40b5ce95f50
import java.util.Scanner; import java.util.HashSet; // 注意类名必须为 Main, 不要有任何 package xxx 信息 public class Main { public static void main(String[] args) { Scanner input = new Scanner(System.in); String next = input.next(); StringBuilder stringBuilder = new StringBuilder(next); HashSet<Character> set = new HashSet<>(); for (int i = 0; i < stringBuilder.length();i++) { set.add(stringBuilder.charAt(i)); } System.out.println(set.size()); } }