abstract data structure-Vector

[iana.bancila]

Please help me to perform this code! I'm beginner and want to know how it's look like!
thank you

To create abstract data type (structure) - vector that comprises a pointer to the target and the number of elements. To define initialization functions, the removal of a vector, set / change the size of the vector, to access to the elements of the vector, a vector calculation module. In the main function to perform addition of two vectors.

[rubberman]

Sounds like school work. We don't do it for you. First, make an effort to solve the assignment. Then, post your code here. We will be happy to help you understand/fix your issues/problems at that point.

[iana.bancila]

smth like this but i cannt do this integrant! please help me!

#include <algorithm>
#include <cstddef>
#include <iostream>
#include <ostream>

template <typename ElementType>
class Vector
{
private:

    ElementType *target;
    std::size_t number_of_elements;

public:

    Vector():
        target(NULL),
        number_of_elements(0)
    {
    }

    Vector(const Vector &v):
        target(new ElementType[v.number_of_elements]),
        number_of_elements(v.number_of_elements)
    {
        std::copy_n(v.target, v.number_of_elements, target);
    }

    Vector & operator = (const Vector &v)
    {
        if (this != &v)
        {
            delete[] target;
            number_of_elements = v.number_of_elements;
            target = new ElementType[v.number_of_elements];
            std::copy_n(v.target, v.number_of_elements, target);
        }

        return *this;
    }

    ~Vector()
    {
        delete[] target;
    }

    std::size_t size() const
    {
        return number_of_elements;
    }

    // warning, this can be destructive
    void resize(std::size_t n)
    {
        number_of_elements = n;

        if (n == 0)
        {
            delete[] target;
            target = NULL;
        }
        else
        {
            ElementType *tmp = new ElementType[n];

            std::copy_n(target, n, tmp);
            delete[] target;
            target = tmp;
        }
    }

    ElementType & operator [] (std::size_t i)
    {
        // your code here
    }

    const ElementType & operator [] (std::size_t i) const
    {
        // your code here
    }

    friend Vector operator + (const Vector &, const Vector &);
    friend std::ostream & operator << (std::ostream &, const Vector &);
};

Vector operator + (const Vector &v1, const Vector &v2)
{
    // your code here
}

std::ostream & operator << (std::ostream &os, const Vector &v)
{
    // your code here
}

int main()
{
    Vector<int> v1, v2;

    v1.resize(3);
    v2.resize(1);

    v1[0] = 3;
    v1[1] = 2;
    v1[2] = 1;
    v2[0] = 0;

    std::cout << v1 + v2 << std::endl; // should print `3 2 1 0'
}

[NathanOliver]

So what exactly are you haveing a problem with? What have you tried?