5.2.1—二叉树的构建—Construct Binary Tree from Preorder and Inorder Traversal

描述
Given preorder and inorder traversal of a tree, construct the binary tree.
Note: You may assume that duplicates do not exist in the tree.

#include "BinaryTree.h"#include<vector>using namespace std;//===由前序和中序构建二叉树BinaryTreeNode* ConBinTreeFromPreAndMid(int pre[],int prebegin, int mid[], int midbegin,int length){if (length <= 0) return NULL;BinaryTreeNode* proot = CreateBinaryTreeNode(pre[prebegin]);ConnectTreeNodes(proot, NULL,NULL);int index = midbegin;for (int i = midbegin; i < midbegin+length; i++){if (pre[prebegin] == mid[i]){index = i; break;}}int prelength = index - midbegin;int lastlength = length - prelength-1;proot->m_pLeft=ConBinTreeFromPreAndMid(pre, prebegin+1, mid, midbegin,prelength);proot->m_pRight = ConBinTreeFromPreAndMid(pre, prebegin+prelength+1,mid ,index + 1,lastlength);return proot;}// ====================测试代码====================int main(){const int n = 9;int pre[n] = { 1, 5, 7, 8, 11, 9, 3, 4,10};int mid[n] = { 7, 5, 8, 1, 3, 9, 4, 11,10};BinaryTreeNode *proot = ConBinTreeFromPreAndMid(pre,0, mid,0,n);PrintTree(proot);DestroyTree(proot);}