/* 这道题的关键是:动态表尽量的选取,知道二叉搜索树中左子树的点都比根节点小,右子树的点都比根节点大 所以当i为根节点,左子树有i-1个点,右子树有n-i个点,左右子树就可以开始递归构建,过程和一开始的过程是一样的, 而左右子树的特征中可以知道的就是点的个数,所以用点的个数作为动态变量就很好. 这样就给我们提供了一个思路:动态规划和树结合的题,由于子问题就是左右树,所以动态变量的选取基本就是考虑题目给出的信息 中,可以从根节点得到左右子树的哪些特征,用这个特征作为动态变量. 二叉搜索树中,都是…

96. Unique Binary Search Trees Given n, how many structurally unique BST's (binary search trees) that store values 1...n? For example, Given n = 3, there are a total of 5 unique BST's.    1         3     3      2      1     \       /     /      / \  …

Given n, how many structurally unique BST's (binary search trees) that store values 1...n? For example,Given n = 3, there are a total of 5 unique BST's. 1 3 3 2 1 \ / / / \ \ 3 2 1 1 3 2 / / \ \ 2 1 2 3 此题是卡塔兰数的一个应用.注意是BST而不是普通的Binary Tree,所以要满足左比根小,…

96. Unique Binary Search Trees https://www.cnblogs.com/grandyang/p/4299608.html 3由dp[1]*dp[1].dp[0]*dp[2].dp[2]*dp[0]相加而成 从2开始 class Solution { public: int numTrees(int n) { vector<); dp[] = ; dp[] = ; ;i <= n;i++){ ;j < i;j++){ dp[i] += dp[j] *…

题目: Given n, how many structurally unique BST's (binary search trees) that store values 1...n? For example,Given n = 3, there are a total of 5 unique BST's. 1 3 3 2 1 \ / / / \ \ 3 2 1 1 3 2 / / \ \ 2 1 2 3 Hide Tags Tree Dynamic Programming Hide Sim…

一天一道LeetCode 本系列文章已全部上传至我的github,地址:ZeeCoder's Github 欢迎大家关注我的新浪微博,我的新浪微博 欢迎转载,转载请注明出处 (一)题目 Given n, how many structurally unique BST's (binary search trees) that store values 1-n? For example, Given n = 3, there are a total of 5 unique BST's. (二)解题…

[Leetcode] Unique binary search trees 唯一二叉搜索树 Unique Binary Search Trees leetcode java 描述 Given n, how many structurally unique BST's (binary search trees) that store values 1...n? For example,Given n = 3, there are a total of 5 unique BST's. 1 3 3 2…

Given n, how many structurally unique BST's (binary search trees) that store values 1...n? For example, Given n = 3, there are a total of 5 unique BST's. 1 3 3 2 1 \ / / / \ \ 3 2 1 1 3 2 / / \ \ 2 1 2 3    法I:后序遍历.同Unique Binary Search Trees II,只是现在…

Unique Binary Search Trees Given n, how many structurally unique BST's (binary search trees) that store values 1...n? For example,Given n = 3, there are a total of 5 unique BST's. 1 3 3 2 1 \ / / / \ \ 3 2 1 1 3 2 / / \ \ 2 1 2 3 Base case: n==0, n==…

Given n, how many structurally unique BST's (binary search trees) that store values 1-n? For example, Given n = 3, there are a total of 5 unique BST's. 1 3 3 2 1 \ / / / \ \ 3 2 1 1 3 2 / / \ \ 2 1 2 3 https://leetcode.com/discuss/24282/dp-solution-i…