import java.util.Scanner;public class T2990 { public static void main(String[] args) { // TODO Auto-generated method stub Scanner scanner = new Scanner(System.in); String str = scanner.nextLine(); char[] str2 = new char[str.length()];// System.out.println(str.length()); ? ? ? ?//write your own codes for(int i=0;i<str.length();i++) { if(str2[i] < 97) { str2[i] =(char)(str2[i]-32);? } if(str2[i] > 97) { str2[i] = (char)(str2[i] - 32); } } System.out.println(new String(str2)); }}我的目的是 輸入 AsDf輸出 aSdF代碼好像是錯的 , 高手指點下