剑指Offer_26_二叉搜索树与双向链表

题目描述

解题思路

实现

/*树结点的定义*/
public class TreeNode {
int val = 0;
TreeNode left = null;
TreeNode right = null;

public TreeNode(int val) {
this.val = val;

}
}
/*实现*/
public class Solution {
public TreeNode Convert(TreeNode pRootOfTree) {
if (pRootOfTree == null) return pRootOfTree;
TreeNode last = null;
recursion(pRootOfTree, last);

//寻找最前面的结点
TreeNode node = pRootOfTree;
while (node.left != null){
node = node.left;
}
return node;
}

private TreeNode recursion(TreeNode pRootOfTree, TreeNode last) {
if (pRootOfTree == null) return last;

//遍历左子树
if (pRootOfTree.left != null)
last = recursion(pRootOfTree.left,last);

//调整当前结点
pRootOfTree.left = last;
if (last != null)
last.right = pRootOfTree;
last = pRootOfTree;

//遍历右子树
if (pRootOfTree.right != null)
last = recursion(pRootOfTree.right,last);

return last;
}
}