给定先序和中序重建二叉树

代码

node* create(int preL, int preR, int inL, int inR){
    if(preL > preR){
        return Null;
    }
    node* root = new node;
    root->data = pre[preL];
    for(int k = inL; k <= inR; k++){
        if(in[k] == pre[preL]) break;
    }
    int numLeft = k - inL;
    root->leftchild = create(preL + 1, preL + numLeft, inL, k - 1);
    root->rightchild = create(preL + numLeft + 1, preR, leftNum + 1, inR);
    return root;
}