hdu 3487 Play with Chain —— splay区间翻转模板

Problem Description
YaoYao is fond of playing his chains. He has a chain containing n diamonds on it. Diamonds are numbered from 1 to n.
At first, the diamonds on the chain is a sequence: 1, 2, 3, …, n.
He will perform two types of operations:
CUT a b c: He will first cut down the chain from the ath diamond to the bth diamond. And then insert it after the cth diamond on the remaining chain.
For example, if n=8, the chain is: 1 2 3 4 5 6 7 8; We perform “CUT 3 5 4”, Then we first cut down 3 4 5, and the remaining chain would be: 1 2 6 7 8. Then we insert “3 4 5” into the chain before 5th diamond, the chain turns out to be: 1 2 6 7 3 4 5 8.

FLIP a b: We first cut down the chain from the ath diamond to the bth diamond. Then reverse the chain and put them back to the original position.
For example, if we perform “FLIP 2 6” on the chain: 1 2 6 7 3 4 5 8. The chain will turn out to be: 1 4 3 7 6 2 5 8

He wants to know what the chain looks like after perform m operations. Could you help him?

Input
There will be multiple test cases in a test data.
For each test case, the first line contains two numbers: n and m (1≤n, m≤3*100000), indicating the total number of diamonds on the chain and the number of operations respectively.
Then m lines follow, each line contains one operation. The command is like this:
CUT a b c // Means a CUT operation, 1 ≤ a ≤ b ≤ n, 0≤ c ≤ n-(b-a+1).
FLIP a b // Means a FLIP operation, 1 ≤ a < b ≤ n.
The input ends up with two negative numbers, which should not be processed as a case.

Output
For each test case, you should print a line with n numbers. The ith number is the number of the ith diamond on the chain.

Sample Input
8 2
CUT 3 5 4
FLIP 2 6
-1 -1

Sample Output
1 4 3 7 6 2 5 8

我们只需要把比最小的小1的放到根节点，比最大的大1的放到根节点的右子节点，这样根节点的右子节点的左子树就是这一段区间，然后z也是这样操作，就可以把这一段区间放到z后面，最后dfs输出

#include<stdio.h>
#include<iostream>
#include<string.h>
#include<algorithm>
using namespace std;
#define keytree ch[ch[root][1]][0]
#define L(x) ch[x][0]
#define R(x) ch[x][1]
#define N 300010
int ch[N][2],pre[N],cnt[N],size[N],val[N],small[N],rev[N],key[N];
int tot,root;
int a[N],n;
void newnode(int &u,int fa,int w,int KEY)
{
    u=++tot;
    ch[u][0]=ch[u][1]=rev[u]=0;
    pre[u]=fa;size[u]=1;
    val[u]=small[u]=w;
    key[u]=KEY;
}
void up(int u)
{
    size[u]=1+size[L(u)]+size[R(u)];
    small[u]=min(val[u],min(small[L(u)],small[R(u)]));
}
void down(int u)
{
    if(rev[u])
    {
        if(L(u))rev[L(u)]^=1;
        if(R(u))rev[R(u)]^=1;
        swap(L(u),R(u));
        rev[u]=0;
    }
}
void rotate(int u,int kind)//kind表示u在fa的哪一边
{
    int fa=pre[u];
    down(fa);down(u);
    ch[fa][kind]=ch[u][!kind];
    pre[ch[u][!kind]]=fa;
    if(pre[fa])ch[pre[fa]][ch[pre[fa]][1]==fa]=u;
    pre[u]=pre[fa];
    ch[u][!kind]=fa;
    pre[fa]=u;
    up(fa);up(u);
}
void splay(int u,int goal)
{
    int fa,kind;
    down(u);
    while(pre[u]!=goal)
    {
        if(pre[pre[u]]==goal)
        {
            down(pre[u]);down(u);
            rotate(u,R(pre[u])==u);
        }
        else
        {
            fa=pre[u];
            down(pre[u]);down(fa);down(u);
            kind=R(pre[fa])==fa;
            if(ch[fa][kind]!=u)//不在同一侧
            {
                rotate(u,!kind);
                rotate(u,kind);
            }
            else
            {
                rotate(fa,kind);
                rotate(u,kind);
            }
        }
    }
    up(u);
    if(goal==0)root=u;
}
int getkth(int u,int k)//第k个键值的点的编号
{
    down(u);
    int s=size[L(u)]+1;
    if(s==k) return u;
    if(s>k) return getkth(L(u),k);
    else return getkth(R(u),k-s);
}
int find(int u,int x)//查找键值为x的点的编号
{                    // 有反转标记时不可用
    down(u);
    if(key[u]==x)return u;
    if(key[u]>x)
    {
        if(!L(u))return -1;
        return find(L(u),x);
    }
    if(key[u]<x)
    {
        if(!R(u))return -1;
        return find(R(u),x);
    }
}
int getpre(int u)
{
    down(u);u=L(u);down(u);
    while(R(u))
    {
        u=R(u);
        down(u);
    }
    return u;
}
int getnext(int u)
{
    down(u);u=R(u);down(u);
    while(L(u))
    {
        u=L(u);
        down(u);
    }
    return u;
}
void del(int x)//删除编号为x的节点
{
    if(cnt[x]>1)
    {
        cnt[x]--;
        return ;
    }
    splay(x,0);
    if(L(root))
    {
        int p=getpre(x);
        splay(p,root);
        R(p)=R(root);
        pre[R(root)]=p;
        root=p;
        pre[p]=0;
        up(root);
    }
    else
    {
        root=R(root);
        pre[root]=0;
    }
}
void build(int &u,int l,int r,int fa)//按pos为键值
{                        //val为数的大小 a存数的大小
    if(l>r)return ;
    int mid=(l+r)>>1;
    newnode(u,fa,a[mid],mid);
    build(L(u),l,mid-1,u);
    build(R(u),mid+1,r,u);
    up(u);
}
void init()
{
    root=tot=0;
    L(root)=R(root)=pre[root]=size[root]=rev[root]=0;
    val[root]=small[root]=N;
    newnode(root,0,N,0);
    newnode(R(root),root,N,N);
    build(keytree,1,n,R(root));
    up(R(root));
    up(root);
}
int getmin(int u,int x)//得到最小值的相对位置
{
    down(u);
    if(val[u]==x) return 1+size[L(u)];
    if(small[L(u)]==x) return getmin(L(u),x);
    if(small[R(u)]==x) return size[L(u)]+1+getmin(R(u),x);
}
//--------------------------------------------------基本操作
int sum=0;
void dfs(int root)
{
    if(root==0)
        return ;
    down(root);
    dfs(ch[root][0]);
    if(key[root]!=0&&key[root]!=N)
    {
        sum++;
        if(sum<n)
            printf("%d ",key[root]);
        else
            printf("%d\n",key[root]);
    }
    dfs(ch[root][1]);
}
int main()
{
    int m;
    while(~scanf("%d%d",&n,&m))
    {
        if(n<0&&m<0)
            break;
        for(int i=1;i<=n;i++)
            a[i]=i;
        char s[5];
        sum=0;
        init();
        int l,r,z;
        while(m--)
        {
            scanf("%s",s);
            if(s[0]=='C')
            {
                scanf("%d%d%d",&l,&r,&z);
                int pos=getkth(root,l);
                splay(pos,0);
                pos=getkth(root,r+2);
                splay(pos,root);
                int now=keytree;
                keytree=0;
                pos=getkth(root,z+1);
                splay(pos,0);
                pos=getkth(root,z+2);
                splay(pos,root);
                keytree=now;
                pre[now]=ch[root][1];
            }
            else
            {
                scanf("%d%d",&l,&r);
                int pos=getkth(root,l);
                splay(pos,0);
                pos=getkth(root,r+2);
                splay(pos,root);
                rev[keytree]^=1;
            }
        }
        dfs(root);
    }
    return 0;
}