java第6次作业

package choujiang;

import java.util.ArrayList;

import java.util.Collections;

import java.util.Random;

public class ChouJiang {

private ArrayList cards;

public void deal(int num){
if (cards==null){
cards=new ArrayList<Integer>();
for(num=1;num<=40;num++){
cards.add(num);
}
}
Collections.shuffle(cards);
}
public void draw(){
Random ra=new Random();
int s =ra.nextInt(cards.size());
System.out.println("一等奖："+ cards.get(s));
cards.remove(cards.get(s));
Collections.shuffle(cards);

for(int i=0;i<2;i++){
int stwo=ra.nextInt(cards.size());
System.out.println("二等奖"+ cards.get(stwo));
cards.remove(cards.get(stwo));
}
Collections.shuffle(cards);
for(int j =0;j<3;j++){
int sthree =ra.nextInt(cards.size());
System.out.println("三等奖"+cards.get(sthree));
cards.remove(cards.get(sthree));

}

}

public static void main(String[] args) {
// TODO Auto-generated method stub
ChouJiang c = new ChouJiang();
c.deal(0);
c.draw();
}

}