Convert a two-fork search tree into a sorted doubly linked list

Analysis:

1. The middle sequence traversal of the two-tree is just the way of the orderly traversal, so it can be processed by the method of the middle order recursion;

2. You can "output" the node to the end of the list in a way similar to the output stream;

3. Local variables can be used to simplify the judgment and optimize the program.

Program:

typedef struct TAGTREENODE_S

{

int nvalue;

Tagtreenode_s* Pleftnode;

Tagtreenode_s* Prightnode;

} treenode_s;

void Appendnode (treenode_s* pnode, treenode_s*& ptailnode)

{

if (Pnode = = NULL)

Return

Ptailnode->prightnode = Pnode;

Pnode->pleftnode = Ptailnode;

Ptailnode = Pnode;

}

void Appendtree (treenode_s* prootnode, treenode_s*& ptailnode)

{

if (Prootnode = = NULL)

Return

Appendtree (Prootnode->pleftnode, Ptailnode);

Appendnode (Prootnode, Ptailnode);

Appendtree (Prootnode->prightnode, Ptailnode);

}

treenode_s* Tolink (treenode_s* prootnode)

{

Treenode_s Headnode;

treenode_s* Ptailnode = &HeadNode;

Ptailnode->prightnode = NULL;

Appendtree (Prootnode, Ptailnode);

Ptailnode->prightnode = NULL;

Ptailnode = headnode->prightnode;

if (ptailnode! = NULL)

Ptailnode->pleftnode = NULL;

return ptailnode;

}

This article is from the "Fool" blog, please be sure to keep this source http://roboter.blog.51cto.com/10249123/1653008

Convert a two-fork search tree into a sorted doubly linked list