Why is my random dynamic array not actually random? [duplicate]

This question already has an answer here:

• Why do I always get the same sequence of random numbers with rand()? 12 answers

I am working on a project for a class and the first step is to generate an array of 10,000 random integers.

When I write the following code:

#include<iostream>
#include<string>
#include<vector>
#include<time.h>
using namespace std;
int main()
{
    int *myarray;
    myarray = new int[10000];
    for (int i = 0; i < 9999; i++)
    {
        myarray[i] = (rand() % 10000);
        // << myarray[i] << " ";
    }
    cout << "A random array of 10,000 integers has been generated.";

        return 0;
}

The first 4 of the numbers is as follows :

0 6843 30 5756

Every time I add more body to my code or recompile these and the rest of the numbers are always the same.

Is there a way to set my random numbers to be random every single time I compile it?

This is in C++ VS 2015.