dataStructure@ Binary Search Tree

#include<iostream>
#include<cstdio>
#include<cstring>
#include<limits>
#include<vector>
using namespace std;
struct BST{
    int key;
    BST *lc, *rc;
    BST(){
        this->key = 0;
        lc = rc = NULL;
    }
    BST(int k){
        this->key = k;
        lc = rc = NULL;
    }
};
BST* newNode(int item){
    BST *tmp = (BST*)malloc(sizeof(BST));
    tmp->key = item;
    tmp->lc = tmp->rc = NULL;
    return tmp;
}
BST* insert(BST *root, int item){
    if(root==NULL) return newNode(item);
    if(item < root->key){
        root->lc = insert(root->lc,item);
    }
    else if(item > root->key){
        root->rc = insert(root->rc,item);
    }
    return root;
}
void inorder(BST *root){
    if(root!=NULL){
        inorder(root->lc);
        cout<< root->key << endl;
        inorder(root->rc);
    }
}
int main(){
    BST *root = new BST(50);
    for(int i=10;i<=200;i+=30){
        root = insert(root, i);
    }
    inorder(root);
    return 0;
}