抽奖系统（二）

package lotterydraw;

import java.util.ArrayList;

import java.util.Collections;

import java.util.Random;

public class lotterDraw {

public static void main(String[] args) {
ArrayList <Integer> number = new ArrayList<>();
Random random = new Random();

for(int i=0;i<2000;i++){
int A=i;
number.add(A);
}
Collections.shuffle(number);
int A = random.nextInt(2000);
System.out.println("一等奖："+number.get(A)+"\n");
number.remove(A);
for(int i=1;i<3;i++){
Collections.shuffle(number);
int B = random.nextInt(2000-i);
System.out.println("二等奖；"+number.get(B)+"\n");
number.remove(B);

}

for(int i=1;i<4;i++){
Collections.shuffle(number);
int B = random.nextInt(1997-i);
System.out.println("三等奖；"+number.get(B)+"\n");
}

}
}