Построить линейный список из входной последовательности чисел и перестроить его

#include <iostream>
 
typedef struct NODE
{
    int m_nVal;
    NODE* m_pPrev;
    NODE* m_pNext;
} NODE;
 
using namespace std;
 
NODE* g_pList = nullptr;
NODE* g_pTail = g_pList;
 
const int N = 100;
 
void Swap(int& n1, int& n2)
{
    int _tn = n1;
    n1 = n2; n2 = _tn;
}
 
void AddNode(int nVal)
{
    NODE* pNode = new NODE();
    memset((void*)pNode, 0x00, sizeof(NODE));
    
    pNode->m_nVal = nVal;
    pNode->m_pPrev = g_pTail;
 
    if (g_pList == nullptr)
        g_pList = g_pTail = pNode;
    else {
        g_pTail->m_pNext = pNode;
        g_pTail = pNode;
    }
}
 
void Push(int nVal) { AddNode(nVal); }
 
int PopBack()
{
    int n_val = (g_pTail != nullptr) ? g_pTail->m_nVal : -1;
    if (g_pTail != nullptr && n_val != -1)
    {
        g_pTail = g_pTail->m_pPrev;
 
        if (g_pTail != nullptr)
            g_pTail->m_pNext = nullptr;
    }
    
    return n_val;
}
 
int PopFront()
{
    int n_val = (g_pList != nullptr) ? g_pList->m_nVal : -1;
    if (g_pList != nullptr && n_val != -1)
        g_pList = g_pList->m_pNext;
 
    return n_val;
}
 
void PrintList(NODE* pList)
{
    for (NODE* pTemp = pList; pTemp != NULL; pTemp = pTemp->m_pNext)
        std::cout << pTemp->m_nVal << " ";
 
    std::cout << endl << endl;
}
 
int main()
{
    for (int index = 0; index < N; index++)
        AddNode(std::rand() % (N - 1) + 1);
 
    PrintList(g_pList);
 
    NODE* pNode = g_pList;
    while (pNode != NULL)
    {
        if (pNode->m_nVal % 2)
        {
            NODE* pNodeFwd = pNode->m_pNext;
            while (pNodeFwd != NULL)
            {
                if (!(pNodeFwd->m_nVal % 2))
                    Swap(pNode->m_nVal, pNodeFwd->m_nVal);
 
                pNodeFwd = pNodeFwd->m_pNext;
            }
        }
 
        pNode = pNode->m_pNext;
    }
 
    PrintList(g_pList);
 
    int n_vals[2] = { 0 };
    while ((n_vals[0] = PopFront()) != -1 && 
           (n_vals[1] = PopBack()) != -1)
        std::cout << n_vals[0] << " <=> " << n_vals[1] << endl;
 
    std::cout << endl;
 
    std::cin.get();
    std::cin.get();
 
    return 0;
}