重建二叉树

前序 a b d c e f

中序 d b a e c f 

重建二叉树，并打印后续 d b e f c a 

#include <stdio.h>
#include <stdlib.h>
#define TREELEN 6
struct NODE{
       NODE* pLeft;
       NODE* pRight;
       char chValue;
       };
       
void Rebuild(char* pPreOrder,char* pInOrder,int nTreeLen,NODE** pRoot){
     
     if(pPreOrder==NULL||pInOrder==NULL||pRoot==NULL)
     return;
     
     
     
     NODE* tmp=new NODE; 
     tmp->chValue=*pPreOrder;
     tmp->pLeft=NULL;
     tmp->pRight=NULL;
     //构造第一个根节点 
     if(*pRoot==NULL)
      *pRoot=tmp;
     if(nTreeLen==1)
      return;
     
     char* pLeftEnd=pInOrder;
     //第二种计算方法会用到 
     char* pOrgInOrder=pInOrder;
     
     int nTempLen=0;
     
     
     while(*pPreOrder != *pLeftEnd){
                      //这里可能有问题;                                             
                      pLeftEnd++;
                      nTempLen++;                      
     }
     
     int leftTreeLen=0,rightTreeLen=0;
     
   // leftTreeLen=int(pLeftEnd-pOrgInOrder); 两种计算方法 
   // rightTreeLen=nTreeLen-leftTreeLen-1;
     leftTreeLen=nTempLen;   
     rightTreeLen=nTreeLen-nTempLen-1;
     if(leftTreeLen>0){
     Rebuild(pPreOrder+1,pInOrder,leftTreeLen,&((*pRoot)->pLeft));
     }
     if(rightTreeLen>0){
     Rebuild(pPreOrder+leftTreeLen+1,pInOrder+leftTreeLen+1,rightTreeLen,&((*pRoot)->pRight));
     }
     
     
     }
void PostOrder(NODE *p)
{
    if(p)
    {
        PostOrder(p->pLeft);
        PostOrder(p->pRight);
        printf("%c",p->chValue);
    }
}

int main(){
    char PreOrder[TREELEN]={'a','b','d','c','e','f'};
    char InOrder[TREELEN]={'d','b','a','e','c','f'};
    
    NODE* pRoot=NULL;
    Rebuild(PreOrder,InOrder,TREELEN,&pRoot);
    
    PostOrder(pRoot);
    system("pause");
    return 0;
    }