LintCode题解之Search Range in Binary Search Tree

1、题目描述

2、问题分析

首先将二叉查找树使用中序遍历的方式将元素放入一个vector，然后在vector 中截取符合条件的数字。

3、代码

 /**
  * Definition of TreeNode:
  * class TreeNode {
  * public:
  *     int val;
  *     TreeNode *left, *right;
  *     TreeNode(int val) {
  *         this->val = val;
  *         this->left = this->right = NULL;
  *     }
  * }
  */

 class Solution {
 public:
     /**
      * @param root: param root: The root of the binary search tree
      * @param k1: An integer
      * @param k2: An integer
      * @return: return: Return all keys that k1<=key<=k2 in ascending order
      */
     vector<int> searchRange(TreeNode * root, int k1, int k2) {
         // write your code here
         vector<int> num ;
         inorder(num, root);

         vector<int> res;
         if( num.size() == )
             return res;
         int i = ;
         int j = num.size() - ;
         while( num[i] < k1) i++;
         while( num[j] > k2) j--;

         for(int k=  i; k <= j; k++){
             res.push_back(num[k]);
         }

         return res;

     }

     void  inorder(vector<int>& nums , TreeNode *root){
         if( root != NULL ){
             inorder(nums, root->left);
             nums.push_back(root->val);
             inorder(nums,root->right);
         }else {
             return ;
         }

     }

 };