public class ShunXunDemo01 {
    public static void main(String[] args) {
        System.out.println("hello1");
        System.out.println("hello1");
        System.out.println("hello1");
        System.out.println("hello1");
        System.out.println("hello1");
    }
}

按顺序打印出来

(if单选择结构)

import java.util.Scanner;

public class IfDemo01 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入内容:");
        String s = scanner.nextLine();

        //equals:判断字符串是否相等
        if (s.equals("Hello")){
            System.out.println(s);
        }
        System.out.println("End");
        scanner.close();
    }
}

判断字符串是否相等,输出的结果不一样