Tree DS implementation in C++ language

Tree.cpp

#include <vector>
#include <list>
#include <map>
#include <set>
#include <queue>
#include <deque>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <cstdlib>
#include <ctime>
using namespace std;

class node 
{
    public:    
        int val;
        node * right, * left;
};

void insert(node ** tree, node * item)
{
        if(!(*tree))
        {
                *tree = item;
                return;
        }
        if(item->val<(*tree)->val)
        {
                insert(&(*tree)->left, item);
        }

        else if(item->val>(*tree)->val)
        {
                insert(&(*tree)->right, item);
        }
}

int isPresent(node* root, int val){
/*
   The structure of the node is as follows:
      class node {
         public:
             node * left, *right;
             int val;
      };
*/
}

int main() {
	node  * _root, * root_curr;
	int root_i=0, root_cnt = 0, root_num = 0;
	_root = NULL;
	cin >> root_cnt;
	for(root_i = 0; root_i < root_cnt; root_i++)
	{
		scanf("%d", &root_num);
		root_curr = (node *)malloc(sizeof(node));

		root_curr->left = root_curr->right = NULL;
		root_curr->val = root_num;

		insert(&_root, root_curr);
	}
	
    int q;
    cin >> q;
    
    while (q--) {
	   int _x; 
	   cin >> _x;
	   cout << isPresent(_root, _x) << endl;
    }
    
	return 0;
}