4 动态输入两个整数，将其交换位置然后再输出。 a=6; b=3; 是用java语言。。必须是java语言

Answer 1

import java.util.Scanner;
public class test{
public static void main(String[] args) {
Scanner s = new Scanner(System.in);
System.out.println("请输入第一个数：");
int a = s.nextInt();
System.out.println("请输入第二个数：");
int b = s.nextInt();
int temp = 0;
temp = a;
a = b;
b = temp;
System.out.println("交换位置后：");
System.out.println(a);
System.out.println(b);
}
}

你说要动态输入还指定a=6; b=3;干什么？运行后，从控制台输入两个数就能交换位置

Answer 2

public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
String str = sc.nextLine();
System.out.println("Please enter:");
str = str.replace(" ", "");
char ch1 = str.charAt(0);
char ch2 = str.charAt(1);
System.out.print(ch2);
System.out.print(ch1);
}