文章目录

• 案例1：买飞机票
• 案例2：找素数
• 案例3：开发验证码
• 案例4：数组元素的复制
• 案例5：评委打分
• 案例6：数字加密
• 案例7：模拟双色球

案例1：买飞机票

import java.util.Scanner;public class Test1 {    public static void main(String[] args) { //用户输入机票原价、月份、仓位类型 Scanner sc = new Scanner(System.in); System.out.println("请输入机票价格："); double money = sc.nextDouble(); System.out.println("请输入机票月份(1-12)："); int month = sc.nextInt(); System.out.println("请输入仓位类型(头等舱/经济舱)"); String type = sc.next(); System.out.println(calc(money, month, type));    }    public static double calc(double money, int month, String type) { if (month >= 5 && month <= 10) {     switch (type) {  case "头等舱":      money *= 0.9;      break;  case "经济舱":      money *= 0.85;      break;  default:      System.out.println("仓位类型输入有误!");     } } else if (month == 11 || month == 12 || month >= 1 && month <= 4) {     switch (type) {  case "头等舱":      money *= 0.7;      break;  case "经济舱":      money *= 0.65;      break;  default:      System.out.println("仓位类型输入有误!");     } } else {     System.out.println("输入错误！"); } return money;    }}

案例2：找素数

public class Test2 {    public static void main(String[] args) { for (int i = 101; i <= 200 ; i++) {     //信号位:标记     boolean flag = true;     for (int j = 2; j < i/2 ; j++) {  if(i % j == 0){      flag = false;      break;  }     }     if(flag == true){  System.out.print(i + "\t");     } }    }}

案例3：开发验证码

import java.util.Random;public class Test3 {    public static void main(String[] args) { String code = createCode(5); System.out.println(code);    }    public static String createCode(int n){ String code = ""; Random r = new Random(); for (int i = 0; i < n; i++) {     //随机生成一个字符,英文大写、小写、数字  (0、1、2)     int type = r.nextInt(3);     switch (type){  case 0:    //大写字符A-Z:65-90      char ch0 = (char) (r.nextInt(26) + 65);      code += ch0;      break;  case 1:      char ch1 = (char) (r.nextInt(26) + 97);      code += ch1;      break;  case 2:      code += r.nextInt(10);      break;     } } return code;    }}

案例4：数组元素的复制

public class Test4 {    public static void main(String[] args) { int[] arr1 = {11,22,33}; int[] arr2 = new int[arr1.length]; copy(arr1,arr2); printArray(arr1); printArray(arr2);    }    public static void copy(int[] arr1,int[] arr2){ for (int i = 0; i < arr1.length; i++) {     arr2[i] = arr1[i]; }    } public static void printArray(int[] arr){ System.out.print("["); for (int i = 0; i < arr.length; i++) {     System.out.print(i == arr.length - 1 ? arr[i] : (arr[i]+",")); } System.out.println("]");    }}

案例5：评委打分

import java.util.Scanner;public class Test5 {    public static void main(String[] args) { int[] scores = new int[6]; Scanner sc = new Scanner(System.in); for (int i = 0; i < scores.length; i++) {     System.out.println("请您输入第" +(i+1)+"位评委的分数");     int score = sc.nextInt();     scores[i] = score; }  int max = scores[0]; int min = scores[0]; int sum = scores[0]; for (int i = 0; i < scores.length; i++) {     if(scores[i] > max){  max = scores[i];     }     if(scores[i] < min){  min = scores[i];     }     sum += scores[i]; } double result = (sum - max - min) *1.0/ (scores.length - 2); System.out.println("最终得分:" + result);    }}

案例6：数字加密

import java.util.Scanner;public class Test6 {    public static void main(String[] args) { //定义一个数组存入需要加密的数据 System.out.println("请输入需要加密的数字个数:"); Scanner sc = new Scanner(System.in); int length = sc.nextInt(); int[] arr = new int[length]; //录入需要加密的数字 for (int i = 0; i < arr.length; i++) {     System.out.println("请输入加密的第"+ (i+1) +"个数字");     int number = sc.nextInt();     arr[i] = number; } //打印数组内容看一下 printArray(arr); //对数组中的数据加密 for (int i = 0; i < arr.length; i++) {     arr[i] = (arr[i] + 5) % 10; } //数组反转 for (int i = 0, j = arr.length-1; i < j; i++, j--) {     int temp = arr[i];     arr[i] = arr[j];     arr[j] = temp; } printArray(arr);    }    //打印数组的方法    public static void printArray(int[] arr){ System.out.print("["); for (int i = 0; i < arr.length; i++) {     System.out.print(i == arr.length-1 ? arr[i] : arr[i]+","); } System.out.println("]");    }}

案例7：模拟双色球

import java.util.Random;import java.util.Scanner;public class Test7 {    public static void main(String[] args) { int[] luckNumbers = createLuckNumber(); int[] userNumbers = userInputNumbers(); judge(luckNumbers,userNumbers);    }    //随机生成中奖号码:6个红球号码(1-33,不重复),随机1个蓝球号码(1-16)    public static int[] createLuckNumber(){ //定义一个动态数组 int[] numbers = new int[7]; //遍历数组,红球号码 Random r = new Random(); for (int i = 0; i < numbers.length-1; i++) {     //注意:判断当前号码是否与之前的重复     while (true){  int data = r.nextInt(33) + 1;  //定义一个flag变量,默认data无重复  boolean flag = true;  for (int j = 0; j < i; j++) {      if(numbers[j] == data){   flag = false;   break;      }  }  if(flag){      numbers[i] = data;      break;  }     } } //蓝球号码 numbers[numbers.length - 1] = r.nextInt(16) + 1; return numbers;    }    //用户选号    public static int[] userInputNumbers(){ int[] numbers = new int[7]; Scanner sc = new Scanner(System.in); for (int i = 0; i < numbers.length - 1; i++) {     System.out.println("请输入第"+(i+1)+"个红球号码(1-33):");      int data = sc.nextInt();      numbers[i] = data; } System.out.println("请输入一个蓝球号码(1-16):"); numbers[6] = sc.nextInt(); return numbers;    }    //判断是否中奖,分别计算红球命中个数和篮球命中个数    public static void judge(int[] luckNumbers,int[] userNumbers){ //定义两个变量分别存储红球、蓝球的命中个数 int redHit = 0; int blueHit = 0; //红球命中统计 for (int i = 0; i < userNumbers.length - 1; i++) {     for (int j = 0; j < luckNumbers.length - 1; j++) {  if(userNumbers[i] == luckNumbers[j]){      redHit ++;      break;  }     } } //篮球命中统计 if(userNumbers[6] == luckNumbers[6]){     blueHit ++; }  //结果显示 System.out.println("中奖号码是:"); printArray(luckNumbers); System.out.println("投注号码是:"); printArray(userNumbers); System.out.println("命中红球个数:" + redHit); System.out.println("命中蓝球个数:" + blueHit); //判断中奖情况 if(blueHit == 1 && redHit < 3){     System.out.println("5元!"); }else if(blueHit == 1 && redHit == 3 || blueHit== 0 && redHit == 4){     System.out.println("10元!"); }else if(blueHit == 1 && redHit == 4 || blueHit== 0 && redHit == 5){     System.out.println("200元!"); }else if(blueHit == 1 && redHit == 5){     System.out.println("3000!"); }else if(blueHit == 0 && redHit == 6){     System.out.println("最高500万!"); }else if(blueHit == 1 && redHit == 6){     System.out.println("最高1000万!"); }else {     System.out.println("未中奖!"); }    }    //打印数组    public static void printArray(int[] arr){ for (int i = 0; i < arr.length; i++) {     System.out.print(arr[i] + "\t"); } System.out.println();    }}

找手机网游