16.2 验证码
/**
* 随机生成指定长度验证码
* @param n 长度
* @return 生成的验证码
*/
public static String createCode(int n){
String code = "";
for (int i = 0; i < n; i++) {
Random random = new Random();
// 生成一个随机字符：英文大写 小写 数字(0、1、2)
int type = random.nextInt(3);
switch (type) {
case 0:
//大写字符 (A 65 - Z 65 + 25)
code += (char) (random.nextInt(26) + 'A');
break;
case 1:
//小写字符
code += (char) (random.nextInt(26) + 'a');
break;
case 2:
//数字字符
code += random.nextInt(10);
break;
}
}
return code;
}
16.3 数字加密
- 实现
import java.util.Scanner;
/**
* @author li
* Create by li on 2022-04-27 19:17
* 数字加密
*/
public class Test03 {
public static void main(String[] args) {
// 需求：数字加密
// 1、定义一个数字存入需要加密的数字
Scanner cin = new Scanner(System.in);
System.out.println("请输入需要加密的数字个数：");
int len = cin.nextInt();
int[] arr = new int[len];
for (int i = 0; i < len; i++) {
System.out.print("请输入第"+(i+1)+"个数字：");
arr[i] = cin.nextInt();
}
// 加密
encryption(arr);
// 打印
printArray(arr);
}
/**
* 打印加密后的数字
* @param arr 存放数字的数组
*/
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("]");
}
public static void encryption(int[] arr) {
for (int i = 0; i < arr.length; i++) {
arr[i] = (arr[i] + 5) % 10;
}
// 反转数组
reverse(arr);
}
public static void reverse(int[] arr) {
for (int i = 0, j = arr.length-1; i < j; i++,j--) {
int t = arr[i];
arr[i] = arr[j];
arr[j] = t;
}
}
}
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- 这里既是加密程序也是解密程序
16.4 模拟双色球
- 业务分析、随机生成一组中奖号码
- 用户输入一组双色球号码
- 判断中奖情况
实现
import java.util.Random;
import java.util.Scanner;
/**
* @author li
* Create by li on 2022-04-27 19:39
* 模拟双色球系统
*/
public class Test04 {
public static void main(String[] args) {
// 调用方法生成一组幸运号码
int[] luckNumbers = createLucNumber();
// 输入用户选取的号码
int [] userNumbers = userInputNumber();
// 判断是否中奖
judge(luckNumbers, userNumbers);
}
/**
* 判断是否中奖
* @param luckNumbers
* @param userNumbers
*/
public static void judge(int[] luckNumbers, int[] userNumbers){
// 命中的红球个数
int redHitNumbers = 0;
int blueHitNumbers = 0;
// 统计命中了红球的个数
for (int i = 0; i < userNumbers.length-1; i++) {
for(int j = 0; j < luckNumbers.length-1; j++){
if (userNumbers[i] == luckNumbers[j]) {
redHitNumbers++;
break;
}
}
}
int n = userNumbers.length;
blueHitNumbers = userNumbers[n-1] == luckNumbers[n-1] ? 1 : 0;
int money = 0;
if(blueHitNumbers == 1){
switch (redHitNumbers) {
case 0:
case 1:
case 2:
money = 5;
break;
case 3:
money = 10;
break;
case 4:
money = 200;
break;
case 5:
money = 3000;
break;
case 6:
money = 10000000;
break;
}
} else {
switch (redHitNumbers) {
case 4:
money = 10;
break;
case 5:
money = 200;
break;
case 6:
money = 5000000;
break;
}
}
System.out.print("开奖号码是：");
printArray(luckNumbers);
System.out.print("您的投注号码是：");
printArray(userNumbers);
System.out.println("您命中了几个红球："+redHitNumbers);
System.out.println("您是否命中蓝球："+(blueHitNumbers == 1 ? "是" : "否"));
if(money == 0){
System.out.println("感谢您为福利事业做出突出贡献！");
} else {
System.out.println("恭喜您，中了"+money+"元");
}
}
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("]");
}
/**
* 输入用户的双色球号码
* @return 双色球号码
*/
public static int[] userInputNumber(){
int[] userNumbers = new int[7];
Scanner cin = new Scanner(System.in);
for (int i = 0; i < userNumbers.length - 1; i++) {
System.out.print("请输入第"+(i+1)+"个红球号码(1-33、不重复)：");
userNumbers[i] = cin.nextInt();
}
System.out.print("请输入蓝球号码(1-16、不重复)：");
userNumbers[userNumbers.length-1] = cin.nextInt();
return userNumbers;
}
/**
* 随机生成一组幸运号码
* @return 生成的号码数组
*/
public static int[] createLucNumber(){
// 随机六个(1-33)不同的数字，随机一个蓝球号码(1-16)
int[] numbers = new int[7];
Random random = new Random();
for (int i = 0; i < numbers.length-1; i++) {
while(true){
int num = random.nextInt(33) + 1;
if (!check(numbers, i+1, num)) {
numbers[i] = num;
break;
}
}
}
// 为第七个位置生成一个蓝球号码
while(true){
int num = random.nextInt(16) + 1;
if (!check(numbers, numbers.length-1, num)) {
numbers[numbers.length-1] = num;
break;
}
}
return numbers;
}
/**
* 判断是否存在重复数组
* @param numbers 双色球数组
* @param n 数组长度
* @param num 判断数字
* @return true:重复、fasle:不重复
*/
public static boolean check(int[] numbers, int n, int num){
for(int i = 0; i < n; i++){
if(numbers[i] == num) {
return true;
}
}
return false;
}
}
