Java Solution with just One HashMap

  • 0

    class RandomizedSet {

    /** Initialize your data structure here. */
    HashMap<Integer, Integer> mapping;
    public RandomizedSet() {
    mapping = new HashMap<Integer, Integer>();
    /** Inserts a value to the set. Returns true if the set did not already contain the specified element. */
    public boolean insert(int val) {
            return false;
        mapping.put(val, val);
        return true;
    /** Removes a value from the set. Returns true if the set contained the specified element. */
    public boolean remove(int val) {
            return false;
        return true;
    /** Get a random element from the set. */
    public int getRandom() {
        int size = mapping.size();
        Set<Integer> keys = mapping.keySet();
        Object[] arr = keys.toArray();
        Random rand = new Random();
        int key = rand.nextInt(size);
        return Integer.valueOf(arr[key].toString());

    } ///

Log in to reply

Looks like your connection to LeetCode Discuss was lost, please wait while we try to reconnect.