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POJ 2352 splay

再撸一发splay。

#include <cstdio>#include <cstring>#include <iostream>#include <algorithm>#include <cstdlib>#include <cmath>#include <utility>#include <vector>#include <queue>#include <map>#include <set>#define max(x,y) ((x)>(y)?(x):(y))#define min(x,y) ((x)>(y)?(y):(x))#define INF 0x3f3f3f3f#define MAXN 100005using namespace std;int cnt=1, rt=0;struct Tree{    int key, size, fa, son[2];    void set(int _key, int _size, int _fa)    {        key=_key;        size=_size;        fa=_fa;        son[0]=son[1]=0;    }}T[MAXN];inline void PushUp(int x){    T[x].size=T[T[x].son[0]].size+T[T[x].son[1]].size+1;}inline void Rotate(int x, int p) //0左旋 1右旋{    int y=T[x].fa;    T[y].son[!p]=T[x].son[p];    T[T[x].son[p]].fa=y;    T[x].fa=T[y].fa;    if(T[x].fa)        T[T[x].fa].son[T[T[x].fa].son[1] == y]=x;    T[x].son[p]=y;    T[y].fa=x;    PushUp(y);    PushUp(x);}void Splay(int x, int To) //将x节点插入到To的子节点中{    while(T[x].fa != To)    {        if(T[T[x].fa].fa == To)            Rotate(x, T[T[x].fa].son[0] == x);        else        {            int y=T[x].fa, z=T[y].fa;            int p=(T[z].son[0] == y);            if(T[y].son[p] == x)                Rotate(x, !p), Rotate(x, p);            else                Rotate(y, p), Rotate(x, p);        }    }    if(To == 0) rt=x;}void Insert(int key){    if(rt == 0)        T[rt = cnt++].set(key, 1, 0);    else    {        int x=rt, y=0;        while(x)        {            y=x;            x=T[x].son[key > T[x].key];        }        T[x = cnt++].set(key, 1, y);        T[y].son[key > T[y].key]=x;        Splay(x, 0);    }}int GetRank(int key){    if(!rt) return 0;    int x=rt, ret=0, y;    while(x)    {        y=x;        if(T[x].key <= key)        {            ret+=T[T[x].son[0]].size+1;            x=T[x].son[1];        }        else            x=T[x].son[0];    }    Splay(y, 0);    return ret;}int n,m,a[MAXN],u[MAXN],x,y,ans[MAXN];int main(){    scanf("%d", &n);    for(int i=0; i<n; i++)    {        scanf("%d%d", &x, &y);        ans[GetRank(x)]++;        Insert(x);    }    for(int i=0; i<n; i++)        printf("%d\n", ans[i]);    return 0;}
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听说splay更常用于区间操作,待我再去挖掘。

POJ 2352 splay