C++手撸红黑树

年后接着撸，撸了part1的简单版本。

#include 
using namespace std;

enum color
{
    BLACK, RED
};

enum state
{
    BLACK_RED_RED_LEFT_LEFT,
    SUITABLE
};

typedef struct node
{
    int value;
    int color;
    node *left;
    node *right;
};

int get(node *n)
{
    if(n->left != NULL && n->left->left != NULL){
        if(n->left->color == RED && n->left->left->color == RED){
            if(n->right != NULL){
                n->right->color = BLACK;
            }
            return BLACK_RED_RED_LEFT_LEFT;
        }
    }
    else{
        return SUITABLE;
    }
}

node* left_left_rotate(node *n)
{
    node* temp = n->left;
    temp->color = BLACK;
    n->color = RED;
    n->left = temp->right;
    temp->right = n;
    return temp;
}

node *insert(node *n, int value)
{
    static bool is_root = true;
    if(n == NULL)
    {
        node *n = new node;
        n->value = value;
        if(is_root == true){
            is_root = false;
            n->color = BLACK;
        }
        else{
            n->color = RED;
        }
        n->left = NULL;
        n->right = NULL;
        return n;
    }
    else
    {
        if(value < n->value)
        {
            n->left = insert(n->left, value);
            int mode = get(n);
            if(mode == BLACK_RED_RED_LEFT_LEFT)
            {
                n = left_left_rotate(n);
            }
        }
        else if(value > n->value)
        {
            n->right = insert(n->right, value);

        }
        return n;
    }
}

int main()
{
    node *root = NULL;

    root = insert(root,10);
    root = insert(root,5);
    root = insert(root,2);
    cout << root->value; 

    system("pause");
    return 0;
}