1 #include <stdio.h>
2
3 typedef int ElementType;
4
5 struct BinarySearchTreeNode
6 {
7 ElementType Element;
8 struct BinarySearchTreeNode *Left;
9 struct BinarySearchTreeNode *Right;
10 };
11
12 //be careful with the names of the node and struct
13 struct BinarySearchTreeNode* BinaryTreeLCA(struct BinarySearchTreeNode* TreeRoot,struct BinarySearchTreeNode* TreeNode_1,struct BinarySearchTreeNode* TreeNode_2)
14 {
15 if(TreeRoot==NULL || TreeRoot==TreeNode_1 || TreeRoot==TreeNode_2)
16 {
17 return TreeRoot;
18 }
19
20 struct BinarySearchTreeNode* NewLeft = BinaryTreeLCA(TreeRoot -> Left,TreeNode_1,TreeNode_2);
21 struct BinarySearchTreeNode* NewRight = BinaryTreeLCA(TreeRoot -> Right,TreeNode_1,TreeNode_2);
22
23 if(NewLeft && NewRight)
24 {
25 return TreeRoot;
26 }
27
28 return NewLeft == NULL ? NewRight : NewLeft;
29 }
30
31 int main()
32 {
33 //struct BinarySearchTreeNode *TreeNode_1;
34 //struct BinarySearchTreeNode *TreeNode_2;
35 //struct BinarySearchTreeNode *TreeNodeLCA;
36 //TreeNode_1 = BinarySearchTreeNodeFind(2,TreeRoot);
37 //TreeNode_2 = BinarySearchTreeNodeFind(-1,TreeRoot);
38 //TreeNodeLCA = BinaryTreeLCA(TreeRoot,TreeNode_1,TreeNode_2);
39 return 0;
40 }
