java 简单粗暴易理解,不考虑别的什么的public class Main { public static void main(String[] args) { Scanner in = new Scanner(System.in); // 注意 hasNext 和 hasNextLine 的区别 while (in.hasNextInt()) { // 注意 while 处理多个 case int a = in.nextInt(); String b = a + ""; String c = ""; for(int i=b.length() -1 ;i>=0;i--){ char t= b.charAt(i); c = c+t; } System.out.println(c); } } }