import java.util.ArrayList;

import java.util.HashSet;

import java.util.List;

import java.util.Set;

/**

* Author : WindAsMe

* File : RandomizedSetResult.java

* Time : Create on 18-9-7

* Location : ../Home/JavaForLeeCode2/RandomizedSetResult.java

* Function : LeetCode No.380

*/

public class RandomizedSetResult {

static class RandomizedSet {

private Set<Integer> set;

private List<Integer> list;

/** Initialize your data structure here. */

public RandomizedSet() {

set = new HashSet<>();

list = new ArrayList<>();

}

/** Inserts a value to the set. Returns true if the set did not already contain the specified element. */

public boolean insert(int val) {

if (set.contains(val))

return false;

else {

set.add(val);

list.add(val);

return true;

}

}

/** Removes a value from the set. Returns true if the set contained the specified element. */

public boolean remove(int val) {

if (set.contains(val)) {

list.remove(Integer.valueOf(val));

set.remove(val);

return true;

} else

return false;

}

/** Get a random element from the set. */

public int getRandom() {

return list.get((int)(Math.random() * list.size()));

}

}

public static void main(String[] args) {

RandomizedSet set = new RandomizedSet();

System.out.println(set.insert(1));

System.out.println(set.remove(2));

System.out.println(set.insert(2));

System.out.println(set.getRandom());

System.out.println(set.remove(1));

System.out.println(set.insert(2));

System.out.println(set.getRandom());

}

}