Simple Vector

template<typename T>
struct Vector {
    T *data;
    int capa, size;
    Vector() {
        capa = 10;
        size = 0;
        data = new T[capa];
    }
    void insert(T v) {
        if (capa == size) {
            auto old = data;
            data = new T[capa * 2];
            for(int i = 0; i < capa; ++i) data[i] = old[i];
            capa *= 2;
            delete[] old;
        }
        data[size++] = v;
    }
    bool erase(T v) { // Erase 1st element that is matched
        for(int i = 0; i < size; ++i) {
            if (data[i] == v) {
                data[i] = data[--size];
                return true;
            }
        }
        return false;
    }
};

Time Complexity

• Insert: $O(1)$
• Erase: $O(n)$