【NOI2004】郁闷的出纳员Splay版

题目连接codevs1286
BZOJ1503，这里数据似乎强大一点，SlowSplay会TLE

学了Splay，，，练练手
多维护一个size域，就可以求k大值辣
昨晚调到接近3点还是RTE/WA，，cry
今天把每个节点加个cnt域就过了
（出现重复的数字的情况

#include<cstdio>
#include<algorithm>
using namespace std;
int m,d,ans;
struct Node{
    int key,s,cnt;//size
    Node *l,*r,*f;//left,right,father
};

class SplayTree{
public:
    void Init(){rt=NULL;}
    int S(Node *T){return (NULL==T)?0:T->s;}
    void Zag(Node *x){//left rotate
        Node *y=x->f;//y is the father of x
        y->r = x->l;
        if (x->l)x->l->f = y;//if x has left child
        x->f =y->f;
        if (y->f){//y is not root
            if (y==y->f->l)y->f->l=x;//y if left child
            else y->f->r=x;//y is right child
        }
        y->f=x;
        x->l=y;
        y->s=S(y->l)+S(y->r)+y->cnt;
        x->s=S(x->l)+S(x->r)+x->cnt;
    }
    void Zig(Node *x){//right rotate
        Node *y=x->f;//y is the father of x
        y->l = x->r;
        if (x->r)x->r->f=y;
        x->f = y->f;
        if (y->f){
            if (y==y->f->l)y->f->l=x;
            else y->f->r=x;
        }
        y->f=x;
        x->r=y;
        y->s=S(y->l)+S(y->r)+y->cnt;
        x->s=S(x->l)+S(x->r)+x->cnt;
    }
    void Splay(Node *x){
        while (x->f){
            Node *p=x->f;
            if (!p->f){
                if (x==p->l)Zig(x);
                else Zag(x);
            }else if (x==p->l){
                if (p==p->f->l){Zig(p);Zig(x);}
                else {Zig(x);Zag(x);}
            }else {//x==p->r
                if (p==p->f->r){Zag(p);Zag(x);}
                else {Zag(x);Zig(x);}
            }
        }
        rt=x;
    }

    void Insert(int x){
        Node *T=rt,*fa=NULL;
        while (T){
            fa=T;
            T->s++;
            if (x==T->key){T->cnt++;Splay(T);return;}
            else if (x<T->key)T=T->l;
            else {T=T->r;}
        }
        T=(Node*)malloc(sizeof(Node));
        T->key=x;
        T->l=T->r=NULL;
        T->f=fa;
        T->s=T->cnt=1;
        if (fa){
            if (fa->key>x)fa->l=T;
            else fa->r=T;
        }
        Splay(T);
    }

    int Findkth(Node *T,int k){//find the K-th biggest number
        if (k< S(T->r)+1)return Findkth(T->r,k);
        else if (k>S(T->r)+T->cnt)Findkth(T->l,k-S(T->r)-T->cnt);
        else {Splay(T);return T->key;}
    }
    void Goaway(Node *&T,Node *fa){
        if (NULL==T)return ;
        if (T->key>=m-d){Goaway(T->l,T);}
        else {
            ans+=S(T->l)+T->cnt;
            T=T->r;
            if (T)T->f=fa;
            if (fa==NULL)rt=T;
            Goaway(T,fa);
        }
        if (T)T->s=T->cnt+S(T->l)+S(T->r);
    }

    void Work(char ch,int x){
        if (ch=='I'&&x>=m)Insert(x-d);
        if (ch=='A')d+=x;
        if (ch=='S'){d-=x;Goaway(rt,NULL);}
        if (ch=='F'){
            if (S(rt) < x)puts("-1");
            else printf("%d\n",Findkth(rt,x)+d);
        }
    }

private:
    Node *rt;//root
};

int main(){
    freopen("fuck.in","r",stdin);
    SplayTree T;
    T.Init();
    int n,x;
    char ch;
    scanf("%d%d\n",&n,&m);
    for (;n--;){
        scanf("%c %d\n",&ch,&x);
        T.Work(ch,x);
    }
    printf("%d\n",ans);
    return 0;
}