Java-黑马Java学习作业-day07综合练习

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练习一飞机票

需求:

​ 机票价格按照淡季旺季、头等舱和经济舱收费、输入机票原价、月份和头等舱或经济舱。

​ 按照如下规则计算机票价格旺季5-10月头等舱9折经济舱8.5折淡季11月到来年4月头等舱7折经济舱6.5折。

代码示例

import java.util.Scanner;

/**
 * @ClassName: codePractice01
 * @Author: Kox
 * @Data: 2023/1/13
 * @Sketch:
 */
public class codePractice01 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入飞机原价格");
        int price = sc.nextInt();
        System.out.print("请输入月份");
        int month = sc.nextInt();
        System.out.print("请输入舱位(0是头等1是经济");
        int level = sc.nextInt();
        if (month >= 5 && month <= 10) {
            price = getPrice(price, level, 0.9, 0.85);
        } else if ((month >= 1 && month <= 4) || (month >= 11 && month <= 12)) {
            price = getPrice(price, level, 0.7, 0.65);
        } else {
            System.out.println("月份输入错误");
        }
        System.out.println(price);
    }

    public static int getPrice(int price, int level , double v0, double v1) {
        if (level == 0) {
            price = (int) (price * v0);
        } else if (level == 1){
            price = (int) (price * v1);
        } else {
            System.out.println("没有这个舱位");
        }
        return price;
    }
}

练习二打印素数

​ 判断101~200之间有多少个素数并输出所有素数。

备注素数就是质数

代码示例

/**
 * @ClassName: cn.kox.practice.codePractice02
 * @Author: Kox
 * @Data: 2023/1/13
 * @Sketch: 找质数
 */
public class codePractice02 {
    public static void main(String[] args) {
        int count = 0;
        for (int i = 101; i <= 200; i++) {
            boolean flag = true;
            for (int j = 2; j < i; j++) {
                if (i % j == 0) {
                    flag = false;
                    break;
                }
            }
            if (flag) {
                System.out.print(i + "\t");
                count++;
            }
        }
        System.out.println("\n有" + count + "个质数。");
    }
}

练习三验证码

需求

​ 定义方法实现随机产生一个5位的验证码

验证码格式

​ 长度为5

​ 前四位是大写字母或者小写字母

​ 最后一位是数字

代码示例

import java.util.Arrays;
import java.util.Random;

/**
 * @ClassName: codePractice03
 * @Author: Kox
 * @Data: 2023/1/13
 * @Sketch: 开发验证码
 */
public class codePractice03 {
    public static void main(String[] args) {
        char[] letter = new char[52];
        for (int i = 0; i < letter.length; i++) {
            if (i <= 25) {
                letter[i] = (char)(97 + i);
            } else {
                letter[i] = (char)(65 + i - 26);
            }
        }
        Random r = new Random();
//        String verify = "";
        char[] verify = new char[5];
        for (int i = 0; i <= 4; i++) {
            int index = r.nextInt(letter.length - 1) + 1;
            if (include(verify, letter, index)) {
                verify[i] = letter[index];
            }
            if (i == 4) {
                index = r.nextInt(10) + 48;
                verify[i] = (char) index;
            }
        }
        System.out.println(Arrays.toString(verify));
    }

    public static boolean include(char[] brr, char[] arr, int num) {
        for (int i = 0; i < brr.length - 1; i++) {
            if (brr[i] == arr[num]) {
                return false;
            }
        }
        return true;
    }
}

练习四复制数组

需求

​ 把一个数组中的元素复制到另一个新数组中去。

代码示例

import java.util.Arrays;

/**
 * @ClassName: codePractice04
 * @Author: Kox
 * @Data: 2023/1/13
 * @Sketch: 数组元素复制
 */
public class codePractice04 {
    public static void main(String[] args) {
        int[] arr = {1, 2, 3, 5, 6, 99, 100};
        int[] brr = new int[arr.length];
        for (int i = 0; i < arr.length; i++) {
            brr[i] = arr[i];
        }
        System.out.println(Arrays.toString(brr));
    }
}

练习五评委打分

需求 :

​ 在唱歌比赛中有6名评委给选手打分分数范围是[0 - 100]之间的整数。选手的最后得分为去掉最高分、最低分后的4个评委的平均分请完成上述过程并计算出选手的得分。

代码示例

import java.util.Arrays;
import java.util.Random;

/**
 * @ClassName: codePractice05
 * @Author: Kox
 * @Data: 2023/1/13
 * @Sketch: 评委打分
 */
public class codePractice05 {
    public static void main(String[] args) {
        int[] arr = new int[6];     // 评委的分数
        Random r = new Random();
        for (int i = 0; i < arr.length; i++) {
            int rScore = r.nextInt(101);
            arr[i] = rScore;
        }
        int score = 0;
        for (int i = 0; i < arr.length; i++) {
            score += arr[i];
        }
        int maxScore = getMax(arr);
        int minScore = getMin(arr);
        double endScore = (double) (score - maxScore - minScore) / (arr.length - 2);
        System.out.println(Arrays.toString(arr));
        System.out.println("去掉一个最高分" + maxScore + "去掉一个最低分" + minScore + "最后得分" + endScore + "分儿。");
    }

    public static int getMax(int[] arr) {
        int maxScore = arr[0];
        for (int i = 1; i < arr.length; i++) {
            if (maxScore < arr[i]) {
                maxScore = arr[i];
            }
        }
        return maxScore;
    }

    public static int getMin(int[] arr) {
        int minScore = arr[0];
        for (int i = 1; i < arr.length; i++) {
            if (minScore > arr[i]) {
                minScore = arr[i];
            }
        }
        return minScore;
    }
}

练习六数字加密

需求

​ 某系统的数字密码大于0比如1983采用加密方式进行传输。

规则如下

​ 先得到每位数然后每位数都加上5 , 再对10求余最后将所有数字反转得到一串新数。

举例

		1	9	8	3
+5		6   14  13  8
%10		6   4   3   8
反转	   8   3   4   6
加密后的结果就是8346

代码示例

/**
 * @ClassName: codePractice06
 * @Author: Kox
 * @Data: 2023/1/14
 * @Sketch: 数字加密
 */
public class codePractice06 {
    public static void main(String[] args) {
        int[] arr = {1, 9 , 8 , 3};
        int number = 0;
        for (int i = arr.length-1; i >= 0; i--) {
            number = number * 10 + getNum(arr[i]);
        }
        System.out.print("加密后的结果就是" + number);
    }

    public static int getNum(int num) {
        num = (num + 5) % 10;
        return num;
    }

}

练习七数字解密

把上一题加密之后的数据进行解密

代码示例

/**
 * @ClassName: codePractice07
 * @Author: Kox
 * @Data: 2023/1/14
 * @Sketch: 数字解密
 */
public class codePractice07 {
    public static void main(String[] args) {
        int[] arr = {8, 3, 4, 6};
        int number = 0;
        for (int i = arr.length-1; i >= 0; i--) {
            number = number * 10 + getNum(arr[i]);
        }
        System.out.println(number);
    }

    public static int getNum(int num) {
        num = (num + 5) % 10;
        return num;
    }
}

练习八抽奖

需求

​ 一个大V直播抽奖奖品是现金红包分别有{2, 588 , 888, 1000, 10000}五个奖金。请使用代码模拟抽奖打印出每个奖项奖项的出现顺序要随机且不重复。打印效果如下随机顺序不一定是下面的顺序

888元的奖金被抽出
588元的奖金被抽出
10000元的奖金被抽出
1000元的奖金被抽出
2元的奖金被抽出

解法一:

import java.util.Arrays;
import java.util.Random;

/**
 * @ClassName: codePractice08
 * @Author: Kox
 * @Data: 2023/1/14
 * @Sketch: 抽奖
 */
public class codePractice08 {
    public static void main(String[] args) {
        int[] arr = {2, 588, 1000, 10000};
        Random r = new Random();
        for (int i = 0; i < arr.length; i++) {
            int index = r.nextInt(arr.length);
            int temp = arr[i];
            arr[i] = arr[index];
            arr[index] =temp;
        }
        System.out.println(Arrays.toString(arr));
    }

}

解法二

import java.util.Random;

/**
 * @ClassName: codeHomework11
 * @Author: Kox
 * @Data: 2023/1/10
 * @Sketch: 题目11
 */
public class codeHomework11 {
    public static void main(String[] args) {
        int[] arr = {2, 588, 1000, 10000};
        int[] brr = new int[arr.length];
        Random r = new Random();
        int flag = 0;
        while (flag < arr.length) {
            int index = r.nextInt(arr.length);
            if (returnNum(brr, arr[index])) {
                brr[flag] = arr[index];
                System.out.println(brr[flag] + "元的奖金被抽出");
                flag++;
            }
        }
    }

    public static boolean returnNum(int[] arr, int num) {
        for (int i = 0; i < arr.length; i++) {
            if (arr[i] == num) {
                return false;
            }
        }
        return true;
    }
}

练习九双色球

代码示例:

import java.util.Arrays;
import java.util.Random;
import java.util.Scanner;

/**
 * @ClassName: codePractice09
 * @Author: Kox
 * @Data: 2023/1/14
 * @Sketch: 双色球系统
 */
public class codePractice09 {
    public static void main(String[] args) {
        int[] red = new int[33];
        red = getArr(red);

        int[] blue = new int[16];
        blue = getArr(blue);

        int[] luckyArr = new int[7];    // 抽出的中奖数组
        Random r = new Random();
        int index = 0;
        while (index < luckyArr.length) {
            int redIndex = r.nextInt(red.length);
            if (getNum(luckyArr, red[redIndex])) {
                luckyArr[index] = red[redIndex];
                index++;
            }
            if (index == luckyArr.length - 1) {
                int blueIndex = r.nextInt(blue.length);
                luckyArr[index] = blue[blueIndex];
                index++;
            }
        }

        // System.out.println("本次奖池号码为" + Arrays.toString(luckyArr));

        int[] userArr = new int[luckyArr.length];   // 用户输入的号码
        Scanner sc = new Scanner(System.in);
        int count = 1;
        while (count <= userArr.length) {
            if (count == userArr.length) {
                System.out.print("输入蓝色球的号码");
                int num = sc.nextInt();
                if (num >= blue[0] && num <= blue[blue.length-1]) {
                    userArr[count-1] = num;
                    count++;
                } else {
                    System.out.println("奖池没有该数字");
                }
            } else {
                System.out.print("输入红色球的第" + count + "个数字");
                int num = sc.nextInt();
                if (num >= red[0] && num <= red[red.length-1]) {
                    if (getNum(userArr,num)) {
                        userArr[count-1] = num;
                        count++;
                    } else {
                        System.out.println("数字输入重复");
                    }
                } else {
                    System.out.println("奖池没有该数字");
                }
            }
        }
        int redCount = 0;
        int blueCount = 0;
        for (int i = 0; i < userArr.length; i++) {
            if (i == userArr.length-1) {
                if (luckyArr[i] == userArr[i]) {
                    blueCount++;
                }
            } else {
                if (luckyArr[i] == userArr[i]) {
                    redCount++;
                }
            }
        }
        System.out.println("本次奖池号码为" + Arrays.toString(luckyArr));
        System.out.println("你竞猜的号码为" + Arrays.toString(userArr));
        System.out.println("红蓝中将次数分别是"+ redCount + ":" + blueCount);
        switch (redCount) {
            case 0,1,2 -> System.out.println(blueCount != 0 ? "六等奖5元" : redCount != 0 ? "六等奖5元" : "无奖");
            case 3 -> System.out.println(blueCount != 0 ? "五等奖10元" : "六等奖5元");
            case 4 -> System.out.println(blueCount != 0 ? "四等奖200元" : "五等奖10元");
            case 5 -> System.out.println(blueCount != 0 ? "三等奖3000元" : "四等奖200元");
            case 6 -> System.out.println(blueCount != 0 ? "一等奖最高1000万" : "二等奖最高500万");
        }

    }

    public static int[] getArr(int[] arr) {
        for (int i = 0; i < arr.length; i++) {
            arr[i] = i + 1;
        }
        return arr;
    }

    public static boolean getNum(int[] arr, int num) {
        for (int i = 0; i < arr.length; i++) {
            if (arr[i] == num) {
                return false;
            }
        }
        return true;
    }


}