根据二叉树的先序和中序遍历重建二叉树

#include <iostream>
#include <cstdio>
using namespace std;
typedef struct BiTNode {
int data;
struct BiTNode *lchild, *rchild;
}BiTNode, *BiTree;

BiTree PreInCreate(char A[], char B[], int l1, int h1, int l2, int h2) {
BiTNode *root = (BiTNode *)malloc(sizeof(BiTNode));
root->data = A[l1];
int i;
for(i = l2; B[i] != root->data; i++);
int llen = i - l2;
int rlen = h2 - i;
if(llen){
root->lchild = PreInCreate(A, B, l1+1, l1+llen, l2, l2+llen-1);
} else {
root->lchild = NULL;
}
if(rlen) {
root->rchild = PreInCreate(A, B, h1-rlen+1, h1, h2-rlen+1, h2);
} else {
root->rchild = NULL;
}
return root;
}
void PreOrder(BiTree T) {
if(T != NULL) {
printf("%c  ", T->data);
PreOrder(T->lchild);
PreOrder(T->rchild);
}
}
void InOrder(BiTree T) {
if(T != NULL) {
InOrder(T->lchild);
printf("%c  ", T->data);
InOrder(T->rchild);
}
}

int main()
{
char A[100], B[100];
printf("please input preorder and inorder :\n");
scanf("%s%s", A+1, B+1);
A[0] = A[0] = 'a';
int len = strlen(A)-1;
BiTNode * root = PreInCreate(A, B, 1, len, 1, len);
PreOrder(root);
cout << endl;
InOrder(root);

return 0;
}
/**
Test：
124356
421536
**/