04、If选择结构

单选择结构

package com.wzt.www.struct;

import java.util.Scanner;

/**
 * @author WZT
 * @create 2021-03-24 16:57
 */
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();

        if (s.equals("Hello")){
    
    
            System.out.println(s);
        }

        System.out.println("End");

        scanner.close();
    }
}

请输入内容：
Hello
Hello
End

Process finished with exit code 0

双选择结构

package com.wzt.www.struct;

import java.util.Scanner;

/**
 * @author WZT
 * @create 2021-03-24 17:01
 */
public class IfDemo02 {
    
    
    public static void main(String[] args) {
    
    
        Scanner scanner = new Scanner(System.in);

        System.out.println("输入成绩");
        int score = scanner.nextInt();

        if (score>=60){
    
    
            System.out.println("及格");
        }else{
    
    
            System.out.println("不及格");
        }


        scanner.close();
    }
}

多选择结构

package com.wzt.www.struct;

import java.util.Scanner;

/**
 * @author WZT
 * @create 2021-03-24 18:40
 */
public class IfDemo03 {
    
    
    public static void main(String[] args) {
    
    
        Scanner scanner = new Scanner(System.in);

        System.out.println("请输入成绩：");

        int score = scanner.nextInt();

        if (score==100){
    
    
            System.out.println("满分");
        }else if (score >=90 && score < 100){
    
    
            System.out.println("优秀");
        }else if (score < 90 && score >= 60){
    
    
            System.out.println("马马虎虎");
        }else if (score >= 0 && score < 60){
    
    
            System.out.println("不及格");
        }else {
    
    
            System.out.println("成绩不合法");
        }



        scanner.close();
    }
}