【splay】hdu 4453 2012杭州赛区A题

http://acm.hdu.edu.cn/showproblem.php?pid=4453

      普通的splay，但是出题人很无聊的给题目加上了很多限制，使得双向链表也可以处理，但是我还是比较喜欢splay这种数据结构，试了一下现在手写无压力。。

//By Lin
#include<cstdio>
#include<cstring>
#include<algorithm>
#define maxn 100050
using namespace std;

struct    SplayNode{
    SplayNode *fa,*ch[2];
    int    key,add,size;
    bool rev;
    SplayNode(int key = 0 ){
        fa = ch[0] = ch[1] = NULL;
        this->key = key;
        size = 1;
        add = 0 , rev = false;
    }
    void clear(){
        if ( ch[0] ) ch[0]->clear();
        if ( ch[1] ) ch[1]->clear();
        delete this;
    }
    void updata(){
        size = (ch[0]?ch[0]->size:0)+(ch[1]?ch[1]->size:0)+1;
    }
    void down(){
        if ( add ){
            if ( ch[0] ) ch[0]->key += add , ch[0]->add += add;
            if ( ch[1] ) ch[1]->key += add , ch[1]->add += add;
            add = 0;
        }
        if ( rev ) {
            swap( ch[0] , ch[1] );
            if ( ch[0] ) ch[0]->rev ^= 1; 
            if ( ch[1] ) ch[1]->rev ^= 1;
            rev = false;
        }
    }
    SplayNode* maxnode(){
        down();
        if ( ch[1] ) return ch[1]->maxnode();
        return this;
    }
    void show(){
        if ( ch[0] ) ch[0]->show();
        printf("%d ", key );
        if ( ch[1] ) ch[1]->show();
    }
}*root,*tmp;
SplayNode* build(int data[],int l,int r,SplayNode* fa = NULL){
    int mid = (l+r)/2;
    SplayNode *ret = new SplayNode(data[mid]);
    ret->fa = fa;
    if ( l<mid ) ret->ch[0] = build(data,l,mid-1,ret);
    if ( mid<r ) ret->ch[1] = build(data,mid+1,r,ret);
    ret->updata();
    return ret;
}
void Rotate(SplayNode* tmp){
    SplayNode* y = tmp->fa;
    if ( tmp->fa = y->fa ) 
        y->fa->ch[y->fa->ch[1]==y] = tmp;
    int d = y->ch[0] == tmp;
    if ( y->ch[d^1] = tmp->ch[d] )
        tmp->ch[d]->fa = y;
    tmp->ch[d] = y;
    y->fa = tmp;
    y->updata();
    tmp->updata();
}
void Splay(SplayNode *tmp, SplayNode *y ) {
    while ( tmp->fa != y )    
        if ( tmp->fa->fa == y ) Rotate(tmp);
        else {
            int d1 = tmp->fa->ch[0] == tmp , d2 = tmp->fa->fa->ch[0] == tmp->fa;
            if ( d1 == d2 ) Rotate(tmp->fa),Rotate(tmp);
            else Rotate(tmp),Rotate(tmp);
        }
}
SplayNode* Select(SplayNode* tmp ,int x){
    tmp->down();
    if ( tmp->ch[0] ){
        if ( tmp->ch[0]->size >= x ) return Select( tmp->ch[0] , x );
        x -= tmp->ch[0]->size;
    }
    if ( x == 1 ) return tmp;
    return Select( tmp->ch[1] , x-1 );
}
SplayNode* Join(SplayNode* l ,SplayNode* r ){
    SplayNode* tmp = l->maxnode();    
    Splay( tmp , NULL );
    tmp->ch[1] = r; 
    r->fa = tmp;
    tmp->updata();
    return tmp;
}
void    delet( int x ) {
    root = Select( root , x );
    Splay( root , NULL );
    root->ch[0]->fa = root->ch[1]->fa = NULL;
    root = Join( root->ch[0], root->ch[1] );
}
void    insert(int key ,int x ){
    root = Select( root,x-1 );
    Splay( root , NULL );
    tmp = Select( root , x );
    Splay( tmp , root );
    tmp->ch[0] = new SplayNode(key);
    tmp->ch[0]->fa = tmp;
    tmp->updata();
    root->updata();
}

int        n,m,K1,K2,data[maxn];
int        main(){
    int tt = 0,x;
    char s[50];
    while ( ~scanf("%d%d%d%d", &n, &m, &K1, &K2 ) ) {
        if ( n == 0 && m == 0 && K1 == 0 && K2 == 0 ) break;
        for (int i = 1; i<=n; i++) scanf("%d", &data[i] );
        root = build( data , 0 , n+1 );
        printf("Case #%d:\n" , ++tt );
        while ( m-- ) {
            scanf("%s", s );
            if ( s[0] == 'q' ) {
                root = Select( root , 2 );
                Splay( root , NULL ); 
                printf("%d\n" , root->key );
            }else 
            if ( s[0] == 'r' ) {
                root = Select(root,1);
                Splay( root , NULL );
                tmp = Select(root,K1+2);
                Splay( tmp , root );
                root->ch[1]->ch[0]->rev ^= 1;
            }else 
            if ( s[0] == 'i' ) {
                scanf("%d", &x );
                insert( x , 3 );
            }else
            if ( s[0] == 'd' ) delet(2); else
            if ( s[0] == 'm' ) {
                scanf("%d", &x );
                if ( x == 1 ) {
                    tmp = Select(root,root->size-1);
                    int key = tmp->key;
                    delet( root->size-1 );
                    insert( key , 2 );
                }
                else {
                    tmp = Select(root,2);
                    int key = tmp->key;
                    delet( 2 );
                    insert( key , root->size );
                }
            }else {
                scanf("%d", &x );
                root = Select( root , 1 );
                Splay( root , NULL );
                tmp = Select( root , K2+2 );
                Splay( tmp , root );
                tmp->ch[0]->add += x;
                tmp->ch[0]->key += x;
            }
        }
        root->clear();
    }
    return 0;
}