java实现抽奖功能解析

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

public class Gift {
 public static void main(String[] args) {

  Scanner sc = new Scanner(System.in);
  System.out.println("请您输入抽奖人数：");
  int n = sc.nextInt();
  Random r1 = new Random();
  System.out.println("幸运儿是："+(r1.nextInt(n)+1));

 }
}

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

public class Gift {
 public static void main(String[] args) {

  Scanner sc = new Scanner(System.in);
  System.out.print("请您输入抽奖人数：");
  int n = sc.nextInt();
  System.out.print("请您输入中奖人数：");
  int num;

  // 判断中奖人数是否符合规则
  while (true) {
   num = sc.nextInt();
   if (n < num) {
    System.out.println("中奖人数 > 抽奖人数，不符合规则。");
    System.out.print("\n请重新输入中奖人数：");

   } else
    break;
  }
  System.out.println("");
  // 创建一个整型数组，来存放抽取的多个幸运儿，来限制不能出现相同序号的幸运儿。
  int[] lucky = new int[num];
  Random r1 = new Random();
  for (int i = 0; i < num; i++) {
   while (true) {
    int luckyMan = r1.nextInt(n) + 1;
    lucky[i] = luckyMan;
    int j = 1;
    if (i == 0) {
     System.out.println("幸运儿是：" + luckyMan);
     break;
    }
    else{
     // 要不等于前面所有的 即 3！=2 && 3！=1 && 3！=0
     if (lucky[i] != lucky[i-1]){
      System.out.println("幸运儿是："+luckyMan);
      break;
     }
    }
   }
  }
 }
}