#include <iostream>
using namespace std;
 
bool AllocArray(int size, int **ptr)
{
    *ptr = new int[size];
    if (ptr != NULL)
        return true;
    else
        return false;
}
 
bool AllocArrayBad(int size, int *ptr)
{
    ptr = new int[size];
    if (ptr != NULL)
        return true;
    else
        return false;
}
 
int main()
{
    int *ptr = NULL;
    AllocArray(10, &ptr);
    // 這裡印出來的不是0
    // 代表成功儲存了配置空間的位置
    cout << ptr << endl;
 
    int *ptr2 = NULL;
    AllocArrayBad(10, ptr2);
    // 這裡印出來的是0
    // 代表並沒有儲存配置空間的位置
    cout << ptr2 << endl;
}

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