leetcode:Unique Binary Search Trees
来源:互联网 发布:linux 安装 tomcat 编辑:程序博客网 时间:2024/05/16 16:04
给出数字n,表示1......n,
问由这些数字可以组成多少种不同的二叉树
直接给出递推式子
ans[i]表示数字i可以组成ans[i]中不同的二叉树
那么 ans[i] = sum(ans[i-j] * [j]) 1<=j<=i
public class Solution { public int numTrees(int n) { int size = 35; int[] ans = new int[size]; Arrays.fill(ans, 0); ans[0] = ans[1] = 1; ans[2] = 2; for(int i = 3; i < ans.length; ++i){ for(int j = 0; j < i; ++j){ ans[i] += ans[j] * ans[i - 1 - j]; } } return ans[n]; }}
0 0
- LeetCode: Unique Binary Search Trees
- LeetCode : Unique Binary Search Trees
- [Leetcode] Unique Binary Search Trees
- [LeetCode]Unique Binary Search Trees
- LeetCode Unique Binary Search Trees
- Leetcode: Unique Binary Search Trees
- LeetCode-Unique Binary Search Trees
- [leetcode] Unique Binary Search Trees
- LeetCode - Unique Binary Search Trees
- [LeetCode] Unique Binary Search Trees
- 【Leetcode】Unique Binary Search Trees
- Leetcode: Unique Binary Search Trees
- 【LeetCode】Unique Binary Search Trees
- Leetcode Unique Binary Search Trees
- Leetcode: Unique Binary Search Trees
- [LeetCode] Unique Binary Search Trees
- Leetcode: Unique Binary Search Trees
- LeetCode | Unique Binary Search Trees
- Qt4.8.2 拖放技术
- Hadoop在反作弊中的应用
- 03_面向对象(一)
- lcd参数理解
- hdu 1698
- leetcode:Unique Binary Search Trees
- 设计模式之模板方法模式(Template Method)摘录
- cocos2d-x-3.1 数据结构之Vector (coco2d-x 学习笔记六)
- oracle中删除表后会有残留,Oracle中清除BIN$开头的垃圾表
- 两个类相互包含引用的问题
- UnixC——进程间通信(IPC)
- QSS的应用
- leetcode:Binary Tree Inorder Traversal
- brand and entreprium