Question about snippet from binary search tree

[An Integer]

I am wondering why the constructor for the binary search tree would want to give left node and right node a nullptr? Does this happen everytime I call a new node in the binary tree? I really don't see how the nodes are then connected. Much appreciated if anyone could please explain this to me.

  struct node {
	int value;
	node* left;
	node* right;
	node(int v) : value(v), left(nullptr), right(nullptr) { }
};

[tpb]

It's just initialized with null pointers. Later on the code will set them to the addresses of new nodes if they belong under this one.

[boring]

nullptr is just used as a starting value. If you're creating a leaf node, then that's just what you need. But if you're creating a node that has left and (or) right child, then you change those pointers. For example:

node *leaf1 = new node(2);
node *leaf2 = new node(3);
node *root = new node(1);
root->left = leaf1;
root->right = leaf2;

[icy1]

Nodes are just clueless actors in a giant play. They know nothing. They need a director/manager who creates them, tells them who they're working with, and kills them without making a mess.