题目： 小虚竹为了给粉丝送福利，决定在参与学习打卡活动的粉丝中抽一位幸运粉丝，送份小礼物。为了公平，要保证抽奖过程是随机的。
1、把参与的人员加到集合中
2、使用Random对象获取随机数
3、把随机数当下标，获取集合中的幸运用户
public class Basics28 {
public static void main(String[] args) {
List<String> luckUserNames = getLuckUserNames();
Random random = new Random();
int luckNum = random.nextInt(6);
System.out.println("幸运的未来大佬是："+luckUserNames.get(luckNum));
}
private static List<String> getLuckUserNames(){
List<String> luckUserNames = new ArrayList<String>();
luckUserNames.add("李慢慢_");
luckUserNames.add("TryAgain-");
luckUserNames.add("team_dog");
luckUserNames.add("Jasonakeke");
luckUserNames.add("学好c语言的小王同学");
luckUserNames.add("Ara～追着风跑");
return luckUserNames;
}
}
随机次数太少，需要优化
需要列出所有人随机命中的次数，显示出来，比较公开公平
public class LuckDraw {
public static void main(String[] args) {
List<String> luckUserNames = getLuckUserNames();
Random random = new Random();
//key:luckNum ,value:count
Map<Integer,Integer> luckNumMap = new HashMap<Integer, Integer>();
for (int i = 0; i < 100; i++) {
int luckNum = random.nextInt(4);
Integer count = luckNumMap.get(luckNum);
if(count==null){
count = 0;
}
++count;
luckNumMap.put(luckNum,count);
}
Integer maxLuckNum = 0;
Integer maxCount =0;
for(Integer luckNum:luckNumMap.keySet()){
if(maxCount<luckNumMap.get(luckNum)){
maxCount = luckNumMap.get(luckNum);
maxLuckNum = luckNum;
}
System.out.println(luckUserNames.get(luckNum)+"同学的幸运值："+luckNumMap.get(luckNum));
}
System.out.println("本周学习打卡积分第一且是幸运的未来大佬是："+luckUserNames.get(maxLuckNum));
}
private static List<String> getLuckUserNames(){
List<String> luckUserNames = new ArrayList<String>();
luckUserNames.add("学好c语言的小王同学");
luckUserNames.add("Ara～追着风跑");
luckUserNames.add("李慢慢_");
luckUserNames.add("Jasonakeke");
return luckUserNames;
}
}
