splay伸展树

#include <iostream>#include <cstdlib>#include <climits>using namespace std;typedef struct node {    int key, val, num, lazy;    long totalVal;    struct node *left, *right, *father;}Node;Node* createNode(int key, int val) {    Node *node = (Node*)malloc(sizeof(Node));    node->key = key;    node->val = val;    node->num = 1;    node->totalVal = val;    node->lazy = 0;    node->left = NULL;    node->right = NULL;    node->father = NULL;    return node;}void update(Node *x) {    //here must initialize    x->num = 1;    x->totalVal = x->val;    if (x->left) {        x->num += x->left->num;        x->totalVal += x->left->totalVal;    }    if (x->right) {        x->num += x->right->num;        x->totalVal += x->right->totalVal;    }}void marking(Node *x, int data) {    x->lazy += data;    x->totalVal += x->num * data;    x->val += data;}void send(Node *x) {    if (x->left)        marking(x->left, x->lazy);    if (x->right)        marking(x->right, x->lazy);    x->lazy = 0;    update(x);}void left_rotate(Node *x) {    Node *p = x->father;    send(p);    send(x);    x->father = p->father;    if (p->father) {        if (p->father->left == p)            p->father->left = x;        else            p->father->right = x;    }    p->right = x->left;    if (x->left)        x->left->father = p;    x->left = p;    p->father = x;    update(p);    update(x);}void right_rotate(Node *x) {    Node *p = x->father;    send(p);    send(x);    x->father = p->father;    if (p->father) {        if (p->father->left == p)            p->father->left = x;        else            p->father->right = x;    }    p->left = x->right;    if (x->right)        x->right->father = p;    x->right = p;    p->father = x;    update(p);    update(x);}//y must be ancestor of x, make x son of yvoid splay(Node *x, Node *y) {    while (x->father != y) {        Node *p = x->father;        if (p->father == y) {            if (p->left == x)                right_rotate(x);            else                left_rotate(x);        }        else {            Node *g = p->father;            if (g->left == p) {                if (p->left == x) {                    right_rotate(p);                    right_rotate(x);                }                else {                    left_rotate(x);                    right_rotate(x);                }            }            else {                if (p->right == x) {                    left_rotate(p);                    left_rotate(x);                }                else {                    right_rotate(x);                    left_rotate(x);                }            }        }    }}Node* bst_insert(Node *root, int key, int val) {    if (!root)        return createNode(key, val);    if (root->key == key)        return root;    send(root);    if (root->key < key) {        root->right = bst_insert(root->right, key, val);        root->right->father = root;    }    else {        root->left = bst_insert(root->left, key, val);        root->left->father = root;    }    update(root);    return root;}Node* bst_find(Node *root, int key) {    if (!root)        return NULL;    if (root->key == key)        return root;    if (root->key < key)        return bst_find(root->right, key);    else        return bst_find(root->left, key);}Node* insert(Node *root, int key, int val) {    root = bst_insert(root, key, val);    Node *temp = bst_find(root, key);    splay(temp, NULL);    return temp;}Node* findPrev(Node *root) {    Node *node = root->left;    while (node->right)        node = node->right;    return node;}Node* findNext(Node *root) {    Node *node = root->right;    while (node->left)        node = node->left;    return node;}Node* deleteN(Node *root) {    Node *prev = findPrev(root);    Node *next = findNext(root);    splay(prev, NULL);    splay(next, prev);    next->left = NULL;    return prev;}Node* findPrev(Node *root, int key) {    Node *temp = bst_find(root, key);    if (temp) {        splay(temp, NULL);        temp = findPrev(temp);        splay(temp, NULL);        return temp;    }    else {        return deleteN(insert(root, key, 0));    }}Node* findNext(Node *root, int key) {    Node *temp = bst_find(root, key);    if (temp) {        splay(temp, NULL);        temp = findNext(temp);        splay(temp, NULL);        return temp;    }    else {        return deleteN(insert(root, key, 0))->right;    }}Node* query(Node *root, int a, int b) {    Node *prev = findPrev(root, a);    Node *next = findNext(prev, b);    splay(prev, NULL);    splay(next, prev);    return prev;}Node* manage(Node *root, int a, int b, int d) {    Node *prev = findPrev(root, a);    Node *next = findNext(prev, b);    splay(prev, NULL);    splay(next, prev);    marking(next->left, d);    root = next->left;    splay(root, NULL);    return root;}Node* deleteN(Node *root, int a, int b) {    root = insert(root, a, 0);    Node *prev = findPrev(root);    root = insert(root, b, 0);    Node *next = findNext(root);    splay(prev, NULL);    splay(next, prev);    next->left = NULL;    return prev;}int main(){    int n, a, b, d;    char c;    Node *root = NULL;    root = insert(insert(root, INT_MAX, 0), INT_MIN, 0);    cin >> n;    for (int i = 0; i < n; i++) {        cin >> c;        switch (c) {        case 'I':            cin >> a >> b;            root = insert(root, a, b);            break;        case 'Q':            cin >> a >> b;            root = query(root, a, b);            cout << root->right->left->totalVal << endl;            break;        case 'M':            cin >> a >> b >> d;            root = manage(root, a, b, d);            break;        case 'D':            cin >> a >> b;            root = deleteN(root, a, b);            break;        default:            break;        }    }    return 0;}