Queue double link struct

//QUEUE//
#include <iostream>
#include "ctime"

using namespace std;

struct dl
{
    dl* prev;
    dl* next;
    int data;
};


dl* pop(dl* ft);
void push(dl** ft, dl** end, int n);

bool empty(dl* ft);
void dl_cout(dl* ft);
void dl_delete(dl** ft);


int main()
{
    srand(time(0));

    dl* ft = NULL;
    dl* end = ft;

    int i, n;

    for (i = 0; i < 10; i++)
    {
        n = rand() % 100;
        push(&ft, &end, n);
    }

    dl_cout(ft);
    ft = pop(ft);
    cout << "Empty? " << std::boolalpha << empty(ft) << endl;
    dl_cout(ft);
    dl_delete(&ft);

    cout << "Empty? " << std::boolalpha << empty(ft) << endl;
}

dl* pop(dl* ft)
{
    dl* ptr = ft;
    if (ft == NULL)
        return NULL;
    else if (ft->next == NULL)
    {
        delete ft;
        return NULL;
    }
    ptr = ft->next;
    delete ft;
    ft = ptr;
    return ft;
}

void push(dl** ft, dl** end, int n)
{
    dl* ptr = new dl;
    ptr->data = n;
    ptr->next = *ft;

    if (*end == NULL)
        * end = ptr;

    *ft = ptr;
}

bool empty(dl* ft) { return ft == NULL; }

void dl_cout(dl* ft)
{
    while (ft != NULL)
    {
        cout << ft->data << " ";
        ft = ft->next;
    }
    cout << endl;
}

void dl_delete(dl** ft)
{
    while (!empty(*ft))
        * ft = pop(*ft);
}