Left-leaning Red-black tree

#include <stdio.h>
#include <iostream>
#include <algorithm>
using namespace std;

struct node *Nil, *Root;

struct node {
    int Key, Value;
    node *ll, *rr;
    bool Red;
    node (int AKey, int AValue, bool IsRed)
        { Key=AKey; Value=AValue; Red=IsRed; ll=rr=Nil; }
    int get(int AKey) {
        if (Key==AKey || this==Nil) return Value;
        return (AKey<Key ? ll : rr)->get(AKey);
    }
    void flip_color()
        { Red^=1; ll->Red^=1; rr->Red^=1; }
};

void init(){
    Root = Nil = new node(-1, -1, 0);
    Nil->ll = Nil->rr = Nil;
}

node* rotate_left(node* x) {
    node *y = x->rr;
    x->rr=y->ll; y->ll=x;
    y->Red=x->Red; x->Red=true;
    return y;
}

node* rotate_right(node* x) {
    node *y=x->ll;
    x->ll=y->rr; y->rr=x;
    y->Red=x->Red; x->Red=true;
    return y;
}

node* insert(node* x, int Key, int Value) {
    if (x==Nil)
        return new node(Key, Value, true);
    if (x->ll->Red && x->rr->Red)
        x->flip_color();

    if (Key==x->Key)
        x->Value = Value;
    else if (Key < x->Key)
        x->ll = insert(x->ll, Key, Value);
    else
        x->rr = insert(x->rr, Key, Value);

    if (x->rr->Red)
        x=rotate_left(x);
    if (x->ll->Red && x->ll->ll->Red)
        x=rotate_right(x);
    return x;
}

ostream& operator << (ostream& cout, node* x){
    if (x==Nil) return cout;
    return cout << "(" << x->ll << x->Key << x->rr << ")";
}

main(){
    init();
    int x;
    while (cin >> x){
        Root = insert(Root, x, 1);
        cout << Root << endl;
    }
}