Compute the height of a binary search tree

Given a list of integers, we can build a binary search tree by inserting them one by one, then compute the height. The input has two lines: the first line is an integer n, the second line contains n integers, for example,

3

5 3 9

The output is the height of the binary search tree in one line. In this case, the output is

1

#include <iostream>#include <stack>#include <vector>#include <algorithm>using namespace std;typedef int T;struct BinaryNode{  T data;  BinaryNode *left, *right;  BinaryNode(T d, BinaryNode *l=NULL, BinaryNode* r=NULL):data(d), left(l), right(r) {};};

int height(BinaryNode* root){    int leftheight,rightheight;    if(root==NULL) return -1;    else{        leftheight = height(root->left);        rightheight = height(root->right);        return (leftheight>rightheight)? (leftheight+1) : (rightheight+1);    }} void recursive_insert(BinaryNode* &p, int data){if(p == NULL){p = new BinaryNode(data);}else if(data < p->data){recursive_insert(p->left,data);}else if(data > p->data){recursive_insert(p->right,data);}}void BST_insert(BinaryNode* &root,int data){recursive_insert(root, data);}int main(){int n;cin>>n;//vector<int> v; int t;BinaryNode* root = NULL;for (int i = 0; i < n; ++i){cin>>t;BST_insert(root,t);}cout<<height(root)<<endl;}