HashSet implementation

class HashSet {
private:
    int size = 1e6+2;
    vector<bool> v;
public:
    /** Initialize your data structure here. */
    HashSet() {
        v.resize(size, false);
    }
    void add(int key) {
        v[key] = true;
    }
    void remove(int key) {
        v[key] = false;
    }
    /** Returns true if this set contains the specified element */
    bool contains(int key) {
        return v[key];
    }
};
/**
 * Your HashSet object will be instantiated and called as such:
 * Your HashSet object will be instantiated and called as such:
 * HashSet* obj = new HashSet();
 * HashSet* obj = new HashSet();
 * obj->add(key);
 * obj->add(key);
 * obj->remove(key);
 * obj->remove(key);
 * bool param_3 = obj->contains(key);
 * bool param_3 = obj->contains(key);
 */
 */