[第二轮] 3/18-3/24 CareerCup 4.9

You are given a binary tree in which each node contains a value. Design an algorithm to print all paths which sum to a given value. Note that a path can start or end anywhere in the tree.

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I suppose dfs could solve that. no good idea...

Using DFS and dynamic programming may solve the problem if I'm allowed to add an extra integer as index to each node.
https://github.com/moophis/careercup/blob/master/4.9.cpp

https://gist.github.com/ThunderXu/5227537
use recursion, find paths start from the current node for every node

https://github.com/1094401996/Ca ... t9/FindSumPath.java
* 此题很好，综合使用了递归和一些编程的小技巧， 我这个智商果断没自己想出来。。。。答案是如此的优雅。。。。
* 第一步：树的高度为N， 建立一个path数组，长度为N + 1
* 第二步：递归遍历每个节点， 对每个节点都findsum函数， on every node, we look "up " to see if
* we have found the sum, that is rather than asking" does this node start a path
* with the sum " , we ask, "does this node complete the path with the sum.This description
* cited from solution is terrific. I must maintain the thinking pattern