构造二叉树

#include <iostream>
using namespace std;

typedef struct BinaryTreeNode
{
    char data;
    BinaryTreeNode * leftChild;
    BinaryTreeNode * rightChild;
}Node;

void MakeBinaryTree(Node** root, char* preOrder, char* midOrder, int length)
{
    if (length == 0)
    {
        (*root) = NULL;
        return;
    }
    (*root) = new Node;
    (*root)->data = *preOrder;

    char * rootplace = strchr(midOrder, (*root)->data);
    if (rootplace == NULL)
    {
        cout <<"input wrong order sample!"<<endl;
    }
    int leftTreeLength = strlen(midOrder) - strlen(rootplace);
    int rightTreeLength = length - leftTreeLength - 1;

    MakeBinaryTree(&(*root)->leftChild, preOrder+1, midOrder, leftTreeLength);
    MakeBinaryTree(&(*root)->rightChild, preOrder+leftTreeLength+1, rootplace+1, rightTreeLength);
}

void PostTraverse(Node* root)
{
    if (root == NULL)
        return;
    PostTraverse(root->leftChild);
    PostTraverse(root->rightChild);
    cout << root->data;
}

int main(int argc, const char** argv)
{
    char pre[] = "abdeijcfg";
    char mid[] = "dbiejafcg";
    Node* r;
    MakeBinaryTree(&r, pre, mid, strlen(pre));
    PostTraverse(r);

    return 0;
}