package choujiang;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Random;

public class Draw {
	private ArrayList<Integer>list;
   public Draw(){
    	list=new ArrayList<Integer>();
   }
    public void deal(int num){
    	//向容器中添加奖券(使用循环)
    		for (int i=1;i<num;i++){
    			list.add(i);
    		}
    	
    	//打乱顺序
    	Collections.shuffle(list);
    	}
    
    public void drawLottery(int n){
    	//产生n个指定范围(0-lise.size)的随机数
    	Random l = new Random();
    	/*
    	 * 获得容器中以产生的随机数为下标的元素的内容
    	 * 即为获奖的奖券的抽奖号,输出
    	 */
    	for(int j=1;j<n;j++){
    		int index =  l.nextInt(list.size());
    
    		System.out.println(list.get(index)+"\t");
    		list.remove(index);
    	}
    	//将已获奖的元素(奖券)从容器中删除
    	System.out.println();
    }
	public static void main(String[] args) {
		// TODO Auto-generated method stub
        Draw a = new Draw();
        a.deal(2000);
        System.out.println(".....一等奖.....");
        a.drawLottery(3);
        System.out.println(".....二等奖.....");
        a.drawLottery(10);
        System.out.println(".....三等奖.....");
        a.drawLottery(15);
	}

}