根据先序序列与中序序列构建二叉树

//根据先序序列与中序序列构建二叉树
BinaryTree* Pre_In_Build(char* pre ,char* in, int size){
    if(!pre || !in || size < 0){
        cout<<"输入出错！"<<endl;
        return NULL;
    }
    int root_index = 0;
    //寻找根结点 
    for(root_index = 0 ; root_index < size ; root_index++){
        if(in[root_index] == pre[0]){
            break;
        }else{
            continue;
        }
    }
    if(root_index == size){
        cout<<"先序序列与中序序列不匹配！"<<endl;
        return NULL;
    }
    //创建根结点 
    BinaryTree* root = this->Creat_Node(pre[0]);
    //递归构建左子树 
    if(root_index > 0){
        root->lchild = this->Pre_In_Build(pre+1,in,root_index); 
    }
    //递归构建右子树 
    if(size - root_index - 1 > 0){
        root->rchild = this->Pre_In_Build(pre+root_index+1,in+1+root_index,size-root_index-1);
    }
    return root;
}

void set(char ch){
    this->data = ch;
    this->lchild = this->rchild = NULL;
}

//创建根节点的函数 
BinaryTree* Creat_Node(char ch){
    BinaryTree* root;
    root = new BinaryTree;
    root->set(ch);
    return root;
}