assigning new array to reference variable

void byReference(int (&p)[3]){
    int q[3] = {8, 9, 10};
    p = q;
}

I want to write function where i can reassign the p with new array. I am not sure if we can do that.

My goal :
i want to change the original array, like we do swapping of two number by call-by reference.

>Solution :

In c++ it is recomended to use std::array for fixed size arrays, and std::vector for a dynamic size arrays.

Both of them can be passed by refernce, to be modified by a function.
This requires the function to declare that the argument is passed by refernce using the & symbol.

See the example below:

#include <array>
#include <vector>

// Get an array (with a fixed size of 3) by refernce and modify it:
void ModifyStdArray(std::array<int, 3> & a) {
    a = std::array<int, 3>{8, 9, 10};
    // or:
    a[0] = 8;
    a[1] = 9;
    // etc.
}

// Get a vector by refernce and modify it:
void ModifyStdVector(std::vector<int> & v) {
    v = std::vector<int>{ 1,2,3,4 };
    // or:
    v.clear();
    v.push_back(1);
    v.push_back(2);
    // etc.
}

int main()
{
    std::array<int, 3> a1;
    // Pass a1 by reference:
    ModifyStdArray(a1);
    // Here a1 will be modified.

    std::vector<int> v1;
    // Pass v1 by reference:
    ModifyStdVector(v1);
    // Here v1 will be modified.
}