Array stack

#include<iostream>
#define MAXSIZE 100
using namespace std;

struct array_stuck
{
    int nTop;
    int nCapacity;
    int *arr;
};

void initial(array_stuck &s);
bool isEmpty(array_stuck s);
bool isFull(array_stuck s);
void push(array_stuck &s, int nData);
int pop(array_stuck &s);


int main()
{
    array_stuck s;
    initial(s);

    push(s, 5);
    push(s, 6);

    cout << pop(s) << endl;
    cout << pop(s) << endl;
    cout << pop(s) << endl;

    system("pause");
    return 0;
}

int pop(array_stuck &s)
{
    if (isEmpty(s))
        return INT_MIN;
    else
        return s.arr[s.nTop--];
}

void push(array_stuck &s, int nData)
{
    if (isFull(s))
        cout << "array_stuck overflow!\n";
    else
        s.arr[++s.nTop] = nData;
}

bool isFull(array_stuck s)
{
    return s.nTop == s.nCapacity - 1;
}

bool isEmpty(array_stuck s)
{
    return s.nTop == -1;
}

void initial(array_stuck &s)
{
    s.nCapacity = MAXSIZE;
    s.nTop = -1;
    s.arr = new int[s.nCapacity];
}