关于动态创建链表节点时new关键字返回地址的精准问询

Great question—let's break this down with clear, concrete terms, using your array example as a reference.

First, let's start with the typical node class you're referring to, just to set context:

class node {
public:
    int data;
    node* next;
    // Default constructor to initialize members
    node() : data(0), next(nullptr) {}
};

When you run the line node* newNode = new node();, here's exactly what happens with the address:

• The new operator first allocates a block of memory on the heap that's large enough to hold the entire node object (this includes space for both the int data and node* next members).
• It then calls the node constructor to initialize those members in that memory block.
• Finally, new returns the starting address of this heap-allocated node object—this is the exact address stored in newNode.

To draw a direct parallel to your array example:

• In int* p = &arr[0];, p stores the starting address of the first int element in the array arr.
• In node* newNode = new node();, newNode stores the starting address of the entire node object that was just created on the heap.

Put another way: newNode points directly to the beginning of the data member (since data is the first member in the class, assuming no compiler padding), but strictly speaking, it's the address of the full node instance. When you use newNode->next, you're accessing the memory offset from that starting address to where the next pointer is stored.

Just to clarify a common point of confusion: this address is not tied to any stack variables—it's a unique address in the heap, allocated specifically for this new node instance, and it will remain valid until you explicitly free it with delete newNode;.

内容的提问来源于stack exchange，提问作者Manav Kampani