hdu-1890-Robotic Sort splay区间翻转

题意：

依次找第i大的数下标pos[i]，然后将区间[i,pos[i]]翻转

分析：

splay树区间翻转

// File Name: ACM/HDU/1890.cpp
// Author: Zlbing
// Created Time: 2013年08月10日 星期六 20时26分39秒
 
#include<iostream>
#include<string>
#include<algorithm>
#include<cstdlib>
#include<cstdio>
#include<set>
#include<map>
#include<vector>
#include<cstring>
#include<stack>
#include<cmath>
#include<queue>
using namespace std;
#define CL(x,v); memset(x,v,sizeof(x));
#define INF 0x3f3f3f3f
#define LL long long
#define REP(i,r,n) for(int i=r;i<=n;i++)
#define RREP(i,n,r) for(int i=n;i>=r;i--)
#define L ch[x][0]
#define R ch[x][1]
#define KT (ch[ ch[rt][1] ][0])
const int MAXN = ;
int cmp(pair<int,int> a,pair<int,int> b){
        if(a.first!=b.first) return a.first<b.first;
        return a.second < b.second;
}
int mp[MAXN];
int id[MAXN];
pair<int,int> num[MAXN];
struct SplayTree {
    int sz[MAXN];
    int ch[MAXN][];
    int pre[MAXN];
    int rt,top;
    inline void down(int x){
        if(flip[x]) {
            flip[ L ] ^= ;
            flip[ R ] ^= ;
            swap(L,R);
            flip[x]=;
        }
    }
    inline void up(int x){
        sz[x]=+sz[ L ] + sz[ R ];
    }
    inline void Rotate(int x,int f){
        int y=pre[x];
        down(y);
        down(x);
        ch[y][!f] = ch[x][f];
        pre[ ch[x][f] ] = y;
        pre[x] = pre[y];
        if(pre[x]) ch[ pre[y] ][ ch[pre[y]][] == y ] =x;
        ch[x][f] = y;
        pre[y] = x;
        up(y);
    }
    inline void Splay(int x,int goal){//将x旋转到goal的下面
        down(x);//防止pre[x]就是目标点，下面的循环就进不去了，x的信息就传不下去了
        while(pre[x] != goal){
            down(pre[pre[x]]); down(pre[x]);down(x);//在旋转之前需要先下传标记，因为节点的位置可能会发生改变
            if(pre[pre[x]] == goal) Rotate(x , ch[pre[x]][] == x);
            else   {
                int y=pre[x],z=pre[y];
                int f = (ch[z][]==y);
                if(ch[y][f] == x) Rotate(x,!f),Rotate(x,f);
                else Rotate(y,f),Rotate(x,f);
            }
        }
        up(x);
        if(goal==) rt=x;
    }
    inline void RTO(int k,int goal){//将第k位数旋转到goal的下面
        int x=rt;
        down(x);
        while(sz[ L ]+ != k) {
            if(k < sz[ L ] +  ) x=L;
            else {
                k-=(sz[ L ]+);
                x = R;
            }
            down(x);
        }
        Splay(x,goal);
    }
    void vist(int x){
        if(x){
            printf("结点%2d : 左儿子  %2d   右儿子  %2d   %2d  flip:%d\n",x,L,R,val[x],flip[x]);
            vist(L);
            vist(R);
        }
    }
    void Newnode(int &x,int c,int f){
        x=++top;flip[x]=;
        L = R = ;  pre[x] = f;
        sz[x]=; val[x]=c;
    }
    inline void build(int &x,int l,int r,int f){
        if(l>r) return ;
        int m=(l+r)>>;
        Newnode(x,num[id[m]].first,f);
        mp[id[m]]=x;
        build(L , l , m- , x);
        build(R , m+ , r , x);
        pre[x]=f;
        up(x);
    }  
 
    inline void init(){
        ch[][]=ch[][]=pre[]=sz[]=;
        rt=top=; flip[]=; val[]=;
    }
    void Del(){
         int t=rt;
         if(ch[rt][]) {
             rt=ch[rt][];
             RTO(,);
             ch[rt][]=ch[t][];
             if(ch[rt][]) pre[ch[rt][]]=rt;
         }
         else rt=ch[rt][];
         pre[rt]=;
         up(rt);
    }
    int flip[MAXN];
    int val[MAXN];
}spt;
int main()
{
    int n;
    while(~scanf("%d",&n))
    {
        if(!n)break;
        spt.init();
        REP(i,,n)
        {
            scanf("%d",&num[i].first);
            num[i].second=i;
        }
        sort(num+,num+n+,cmp);
        REP(i,,n)
            id[num[i].second]=i;
        spt.build(spt.rt,,n,);
 
        REP(i,,n)
        {
            spt.Splay(mp[i],);
            int ans=i+spt.sz[spt.ch[spt.rt][]];
            spt.flip[spt.ch[spt.rt][]]^=;
            spt.Del();
            if(i==)printf("%d",ans);
            else printf(" %d",ans);
        }
        printf("\n");
    }
    return ;
}