Quasetion two Data Structure

// ConsoleApplication2.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include"string"
#define size 5
using namespace std;
struct node
{
    int data;
    node* next;
};
struct stack
{
    int data[size];
    int top;
};
struct queue
{
    int data[size];
    int front, rear;
};
void add(node*& head, node*& tail, int item)
{
    node* newNode = new node;
    newNode->data = item;
    newNode->next = NULL;
    if (head == NULL)
    {
        head = tail = newNode;
        return;
    }
    else
    {
        newNode->next = head;
        head = newNode;
    }
}

void enqueue(queue* q, int item)
{
    if (q->rear > size - 1)
    {
        cout << "queue is full\n";
        return;
    }
    else
    {
        q->rear++;
        q->data[q->rear] = item;
        if (q->front == -1)
            q->front = 0;
    }
}
int dqueue(queue* q)
{
    int item;
    if (q->front == -1)
    {
        return -1;
    }
    else if(q->front<q->rear)
    {
        item = q->data[q->front];
        q->front++;
        return item;
    }
    else if (q->front == q->rear)
    {
        item = q->data[q->front];
        q->front = q->rear = -1;
        return item;
    }
}
void push(stack *stk,int item)//push function for linked stack
{

    if (stk->top > size-1)
    {
        cout << "stack is full";
        return;
    }
    else
    {
        stk->data[stk->top++] = item;
    }
}
int pop(stack* stk)
{
    int item;
    if (stk->top == -1)
        return -1;
    else
    {
        item = stk->data[--stk->top];
        return item;
    }
}
void store(node*& head, stack* stk, queue* q)
{
    node* temp;
    temp = head;
    if (head == NULL)
    {
        cout << "list is empty\n";
        return;
    }
    else
    {
        while (temp != NULL)
        {
            if (temp->data % 2 == 0)
            {
                push(stk, temp->data);
            }
            else if (temp->data % 2 == 1)
            {
                enqueue(q, temp->data);
            }
            temp = temp->next;
        }
    }
}
int main()
{
    node* head, * tail;
    head = tail = NULL;
    stack stk;
    stk.top = -1;
    queue q;
    q.front = -1;
    q.rear = -1;
    int item, i;
    for (i = 0; i < 10; i++)
    {
        cout << "Enter item "; cin >> item;
        add(head, tail, item);
    }
    store(head, &stk, &q);
    cout << "\n\nData of stack\n\n";
    for (i = 0; i < size + 1; i++)
    {
        item = pop(&stk);
        if (item == -1)
            cout << "\nstack is empty";
        else
            cout << "\ndata is : " << item;
    }
    cout << "\n\nData of queue\n\n";
    for (i = 0; i < size + 1; i++)
    {
        item = dqueue(&q);
        if (item == -1)
            cout << "\nqueue is empty";
        else
            cout << "\ndata is : " << item;
    }
}