Java面试题二

java基础练习：选择结构（if、switch）

练习1：提示用户输入三个整数，判断并输出最大值、最小值

package com.mhg;

import java.util.Scanner;

/**
 * @Time :2022/2/16 20:14
 * @Author :MHG
 **/
public class TestDay08 {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);

        System.out.print("请输入第一个整数：");
        int a = input.nextInt();
        System.out.print("请输入第二个整数：");
        int b = input.nextInt();
        System.out.print("请输入第三个整数：");
        int c = input.nextInt();

        int max,min;
        // 先比较a和b
        if (a > b) {
            max = a ;
            min = b ;
        } else {
            max = b ;
            min = a ;
        }

        // 然后将c与max、min进行比较
        if (c > max) {
            max = c ;
        } else {
            min = c ;
        }

        System.out.print("最大值：" + max);
        System.out.print("最小值：" + min);
    }
}

练习2：如果今天是周日且晴天，就出去嗨。如果今天是周日但不是晴天，睡懒觉。如果今天不是周日，继续996。

说明：天气、星期几的变量，自己定义即可；主要练习if嵌套

package com.mhg;

import java.util.Scanner;

/**
 * @Time :2022/2/17 20:57
 * @Author :MHG
 **/
public class TestDay09 {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.print("请输入星期数（整数 1-7）：");
        int today = input.nextInt();

        if (today == 7) {

            System.out.print("请输入天气：");
            String weather = input.next();

            if(weather.equals("晴天")) {
                System.out.print("今天周末，出去嗨！！！");
            }else {
                System.out.print("今天休息，家里睡懒觉。");
            }
        }else {
            System.out.print("继续996。");
        }
    }
}

练习3：由键盘输入三个整数分别存入变量num1、num2、num3，对它们进行排序(使用 if-else if-else)，并且从小到大输出。

package com.mhg;

import java.util.Scanner;

/**
 * @Time :2022/2/18 15:51
 * @Author :MHG
 **/
public class TestDay10 {
    public static void main(String[] args) {
        System.out.println("请输入三个整数。");
        Scanner scanner = new Scanner(System.in);
        System.out.print("num1=");
        int num1 = scanner.nextInt();
        System.out.print("num2=");
        int num2 = scanner.nextInt();
        System.out.print("num3=");
        int num3 = scanner.nextInt();
        System.out.println("您输入的三个整数分别为:" + num1 + "," + num2 + "," + num3);
        if (num1 <= num2) {
            if (num3 <= num1) {
                System.out.println(num3 + "," + num1 + "," + num2);
            } else if (num3 >= num2) {
                System.out.println(num1 + "," + num2 + "," + num3);
            } else {
                System.out.println(num1 + "," + num3 + "," + num2);
            }
        } else {
            if (num3 <= num2) {
                System.out.println(num3 + "," + num2 + "," + num1);
            } else if (num3 >= num1) {
                System.out.println(num2 + "," + num1 + "," + num3);
            } else {
                System.out.println(num2 + "," + num3 + "," + num1);
            }
        }
    }
}

练习4：提示用户输入三角形的边a、b、c，范围必须在 [1,100) 之间，判断三角形的类型：1.非三角形；2.等边三角形；3.直角三角形；4.等腰三角形；5.普通三角形。

package com.mhg;

import java.util.Scanner;

/**
 * @Time :2022/2/19 14:33
 * @Author :MHG
 **/
public class TestDay11 {
    public static void main(String[] args) {
        Scanner input = new Scanner(System.in);
        System.out.print("请输入第一条边: ");
        int a = input.nextInt();
        System.out.print("请输入第二条边: ");
        int b = input.nextInt();
        System.out.print("请输入第三条边: ");
        int c = input.nextInt();
        if (a <1 || a>=100 || b<1 || b>=100 || c<1 || c>=100) {
            System.out.println("数据无效! ");
        }else {
                if(a+b<=c || a+c<=b || b+c<=a){
                    System.out.println("非三角形! ");
                } else {
                    if (a==b && a==c){
                        System.out.println("等边三角形! ");
                    }else if(a*a+b*b==c*c || a*a+c*c==b*b || b*b+c*c==a*a){
                        System.out.println("直角三角形! ");
                    }else if(a==b || a==c || b==c){
                        System.out.println("等腰三角形! ");
                    }else{
                        System.out.println("普通三角形! ");
                    }
                }
            }

        }
}

练习6：周一跑步，周二、三、四打羽毛球，周五游泳，其它休息