[Leetcode] [JavaScript] Unique Binary Search Trees II

Unique Binary Search Trees II

Given n, generate all structurally unique BST's (binary search trees) that store values 1 ... n.

For example,
Given N = 3, your program should return all 5 unique BST ' s shown below.

   1         3     3      2      1    \//      /\           3     2     1      1   3      2    /     /       \                    2     1         2                 3

https://leetcode.com/problems/unique-binary-search-trees-ii/#

Generates a two-fork sort tree of N nodes.

Follow the same idea, divide and conquer, from 1 to n traversal, select the current point for the root, smaller than the root in the left subtree, larger than the root in the right sub-tree.

Http://www.cnblogs.com/Liok3187/p/4948510.html

1 /**2 * Definition for a binary tree node.3 * Function TreeNode (val) {4 * This.val = val;5 * This.left = This.right = null;6  * }7  */8 /**9 * @param {number} nTen * @return {treenode[]} One  */ A varGeneratetrees =function(n) { -     returnGettree (1, n); -  the     functionGettree (start, end) { -         varRET =[], I, J, K, left, right, node; -         if(Start >end) { -             return[NULL]; +}Else if(Start = = =end) { -             return[NewTreeNode (start)]; +         } A          for(i = start; I <= end; i++){ atleft = Gettree (Start, i-1); -right = Gettree (i + 1, end); -              for(j = 0; J < Left.length; J + +){ -                  for(k = 0; k < right.length; k++){ -node =NewTreeNode (i); -Node.left =Left[j]; inNode.right =Right[k]; - Ret.push (node); to                 } +             } -         } the         returnret; *     } $};

[Leetcode] [JavaScript] Unique Binary Search Trees II