26.二叉搜索树与双向链表

题目描述

输入一棵二叉搜索树，将该二叉搜索树转换成一个排序的双向链表。要求不能创建任何新的结点，只能调整树中结点指针的指向。

题目解答

/**
public class TreeNode {
    int val = 0;
    TreeNode left = null;
    TreeNode right = null;

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

    }

}
*/
public class Solution {
    private TreeNode head=null;
    private TreeNode end=null;
    public TreeNode Convert(TreeNode pRootOfTree) {
        ConvertSub(pRootOfTree);
        return head;
    }
    public void ConvertSub(TreeNode pRootOfTree){
        if(pRootOfTree==null){
            return;
        }
        ConvertSub(pRootOfTree.left);
        if(end==null){
            head=pRootOfTree;
            end=pRootOfTree;
        }else{
            end.right=pRootOfTree;
            pRootOfTree.left=end;
            end=pRootOfTree;
        }
        ConvertSub(pRootOfTree.right);
    }
}