Treap

#include <iostream>
#include <cstdlib>
#include <cstring>
#include <queue>
#include <cstdio>
#include <algorithm>
#include <map>
#define LL long long

using namespace std;

struct Treap_node
{
    Treap_node *left,*right;
    int value,fix; //the value and the random fix value
}*root;

void Treap_left_rotate(Treap_node *&a)
{
    Treap_node *b = a->right;
    a->right = b->left;
    b->left = a;
    a = b;
}

void Treap_right_rotate(Treap_node *&a)
{
    Treap_node *b = a->left;
    a->left = b->right;
    b->right = a;
    a = b;
}

void Treap_insert(Treap_node*&p, int value)
{
    if(!p)
    {
        p = new Treap_node;
        p->value = value;
        p->fix = rand();
        p->left = p->right = NULL;
    }
    else if(value <= p->value)
    {
        Treap_insert(p->left,value);
        if(p->left->fix < p->fix)
            Treap_right_rotate(p);
    }
    else
    {
        Treap_insert(p->right,value);
        if(p->right->fix < p->fix)
            Treap_left_rotate(p);
    }
}

void Treap_delete(Treap_node* &p,int value)
{
    if(value < p->value)
        Treap_delete(p->left,value);
    else if(value > p->value)
        Treap_delete(p->right,value);
    else
    {
        if(!p->right || !p->left) //link nodes or have no child node
        {
            Treap_node *t;
            t = p;
            if(!p->right)
                p = p->left;
            else
                p = p->right;
            delete t;
        }
        else
        {
            if(p->left->fix < p->right->fix)
            {
                Treap_right_rotate(p);
                Treap_delete(p->right,value);
            }
            else
            {
                Treap_left_rotate(p);
                Treap_delete(p->left,value);
            }
        }
    }
}