红黑树

 

#include<stdio.h>
#include<stdlib.h>

#define INFO 0x3ff
#define NEINFO -0x3ff

typedef enum ColorType{
    Black,Red
}ColorType;

struct Node{
    int data;
    ColorType Colory;
    struct Node *Left,*Right;
};
typedef struct Node* RedBlackTree; 
typedef RedBlackTree Position;

Position NUllNode = NULL;

RedBlackTree Init()
{
    RedBlackTree T;
    if(NUllNode==NULL)
    {
        NUllNode=(RedBlackTree)malloc(sizeof(struct Node));
        if(NUllNode==NULL) printf("Out of Space!!!");
        NUllNode->Left=NUllNode->Right=NUllNode; 
        NUllNode->data=INFO;
        NUllNode->Colory=Black;
    }
    
    T=(RedBlackTree)malloc(sizeof(struct Node));
    if(T==NULL) printf("Out of Space!!!");
    T->Left=T->Right=NUllNode;
    T->data=NEINFO;
    T->Colory=Black;
    return T;
}

RedBlackTree SingleLeftRotate(RedBlackTree T)
{
    RedBlackTree p=T->Left;
    T->Left=p->Right;
    p->Right=T;
    return p;
}

RedBlackTree SingleRightRotate(RedBlackTree T)
{
    RedBlackTree p=T->Right;
    T->Right=p->Left;
    p->Left=T;
    return p;
}

RedBlackTree Rotate(int Item,RedBlackTree T)
{
    if(Item<T->data)
    {
        return T->Left=(Item<T->Left->data?
        SingleLeftRotate(T->Left):
        SingleRightRotate(T->Left));
    }
    else
    {
        return T->Right=(Item>T->Right->data?
        SingleRightRotate(T->Right):
        SingleLeftRotate(T->Right));
    }
}

static RedBlackTree X,P,GP,GPP;

static void HandleReorient(int Item,RedBlackTree T)
{
    X->Colory=Red;
    X->Left->Colory=Black;
    X->Right->Colory=Black;
    
    if(P->Colory==Red)
    {
        X->Colory=Black;
        if((Item<GP->data)!=(Item<P->data))
        P=Rotate(Item,GP);
        X=Rotate(Item,GPP);
        X->Colory=Black;
    }
    
    T->Right->Colory=Black;
}

RedBlackTree Insert(int Item,RedBlackTree T)
{
    X=P=GP=T;
    NUllNode->data=Item;
    while(Item!=X->data)
    {
        GPP=GP;GP=P;P=X;
        if(Item<X->data)
        {
            X=X->Left;
        }
        else
        {
            X=X->Right;
        }
        
        if(X->Left->Colory==Red&&X->Right->Colory==Red) HandleReorient(Item,T);
    }
    
    if(X!=NUllNode) return NUllNode;
    
    X=(RedBlackTree)malloc(sizeof(struct Node));
    if(X==NULL) printf("Out of Space!!!");
    X->Left=X->Right=NUllNode;
    X->data=Item;
    
    if(Item<P->data) P->Left=X;
    else P->Right=X;
    
    HandleReorient(Item,T);
    return T;
}

void PrePrint(RedBlackTree T)
{
    if(T!=NUllNode)
    {
        printf("%d ",T->data);
        PrePrint(T->Left);
        PrePrint(T->Right);
    }
}

int main(void)
{
    RedBlackTree T=Init();
    int n,i,x;
    scanf("%d",&n);
    for(i=0;i<n;i++)
    {
        scanf("%d",&x);
        T=Insert(x,T);
        //printf("-11");
    }
    
    PrePrint(T->Right);
    return 0;
}