Leetcode#106 Construct Binary Tree from Inorder and Postorder Traversal

原题地址

二叉树基本操作

[       ]O[              ]

[       ][              ]O

代码：

 TreeNode *restore(vector<int> &inorder, vector<int> &postorder, int ip, int pp, int len) {
   if (len == )
     return NULL;

   TreeNode *node = new TreeNode(postorder[pp + len - ]);

   if (len == )
     return node;

   int leftLen = ;
   while (inorder[ip + leftLen] != postorder[pp + len - ])
     leftLen++;
   node->left = restore(inorder, postorder, ip, pp, leftLen);
   node->right = restore(inorder, postorder, ip + leftLen + , pp + leftLen, len - leftLen - );

   return node;
 }

 TreeNode *buildTree(vector<int> &inorder, vector<int> &postorder) {
   return restore(inorder, postorder, , , inorder.size());
 }