hdu3487Play with Chain(splay)

链接

简单的两种操作，一种删除某段区间，加在第I个点的后面，另一个是翻转区间。都是splay的简单操作。

悲剧一：pushdown时候忘记让lz=0

悲剧二：删除区间，加在某点之后的时候忘记修改其父亲节点。

#include <iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<stdlib.h>
#include<vector>
#include<cmath>
#include<queue>
#include<set>
using namespace std;
#define N 300010
#define LL long long
#define INF 0xfffffff
#define key_value ch[ch[root][1]][0]
const double eps = 1e-8;
const double pi = acos(-1.0);
const double inf = ~0u>>2;
using namespace std;
struct splay_tree
{
    int pre[N],size[N];
    int ch[N][2];
    int root,tot,num,tot1;
    int key[N],lz[N];
    void dfs(int x)
    {
        if(x)
        {
            dfs(ch[x][0]);
            printf("结点%2d:左儿子 %2d 右儿子 %2d 父结点 %2d size=%2d,key=%2d lz = %d
",
                   x,ch[x][0],ch[x][1],pre[x],size[x],key[x],lz[x]);
            dfs(ch[x][1]);
        }
    }
    void debug()
    {
        printf("root:%d
",root);
        dfs(root);
    }
//以上用于debug*/
    void newnode(int &x,int v,int fa)//新建一结点
    {
        x = ++tot;
        ch[x][0]=ch[x][1] = 0;
        pre[x] = fa;
        lz[x] = 0;
        size[x] = 1;
        key[x] = v;
    }
    void pushdown(int w)
    {
        if(lz[w])
        {
            int l = ch[w][0],r = ch[w][1];
            swap(ch[w][0],ch[w][1]);

            lz[l]^=lz[w];
            lz[r]^=lz[w];
            lz[w] = 0;
        }
    }
    void pushup(int w)//由儿子更新其父亲
    {
        size[w] = size[ch[w][0]]+size[ch[w][1]]+1;
        //cout<<s[w][0]<<" "<<s[w][1]<<endl;
    }
    void rotate(int r,int kind)//旋转操作，根据kind进行左旋和右旋
    {
        int y = pre[r];
        pushdown(y);
        pushdown(r);
        ch[y][!kind] = ch[r][kind];
        pre[ch[r][kind]] = y;
        if(pre[y])
        {
            ch[pre[y]][ch[pre[y]][1]==y] = r;
        }
        pre[r] = pre[y];
        ch[r][kind] = y;
        pre[y] = r;
        pushup(y);
        pushup(r);
    }
    void splay(int r,int goal)//将r结点旋至goal下
    {
        pushdown(r);
        while(pre[r]!=goal)
        {
            if(pre[pre[r]]==goal)
            {
                rotate(r,ch[pre[r]][0]==r);
            }
            else
            {
                int y = pre[r];
                int kind = (ch[pre[y]][0]==y);
                if(ch[y][kind]==r)
                {
                    rotate(r,!kind);
                    rotate(r,kind);
                }
                else
                {
                    rotate(y,kind);
                    rotate(r,kind);
                }
            }
        }
        pushup(r);
        if(goal==0) root = r;
    }
    int get_k(int k)//得到第k个的结点
    {
        int r = root;
       pushdown(r);
        while(size[ch[r][0]]+1!=k)
        {
            if(size[ch[r][0]]>=k)
                r = ch[r][0];
            else
            {
                k-=(size[ch[r][0]]+1);//根据左右结点的数量来确定第k个节点在哪里
                r = ch[r][1];
            }
            pushdown(r);
        }
        pushup(r);
        return r;
    }
    void cut(int l,int r,int k)
    {
        splay(get_k(l),0);
        splay(get_k(r+2),root);
        pushdown(ch[root][1]);
        int nod = key_value;
        ch[ch[root][1]][0] = 0;
        pre[nod] = 0;
        pushup(ch[root][1]);
        pushup(root);
        //debug();
        splay(get_k(k),0);
        splay(get_k(k+1),root);
        ch[ch[root][1]][0] = nod;
        pre[nod] = ch[root][1];
        pushup(ch[root][1]);
        pushup(root);
       // debug();
    }
    void filp(int l,int r)
    {
        //cout<<get_k(l)<<" "<<get_k(r+2)<<endl;
        splay(get_k(l),0);
        splay(get_k(r+2),root); //cout<<","<<endl;debug();
        lz[key_value]^=1;
        //swap(ch[key_value][0],ch[key_value][1]);
        pushup(ch[root][1]);
        pushup(root);
    }
    void work(int n)
    {
        int i;
        for(i = 1 ;i < n ;i++)
        {
            printf("%d ",key[get_k(i+1)]);
        }
        printf("%d
",key[get_k(n+1)]);
        //debug();
    }
    void build(int &x,int l,int r,int fa)
    {
        int m = (l+r)>>1;
        if(l>r) return ;
        newnode(x,m,fa);
        build(ch[x][0],l,m-1,x);
        build(ch[x][1],m+1,r,x);
        pushup(x);
    }
    void init(int o)
    {
        size[0] = ch[0][0] = ch[0][1] =  key[0] = lz[0] = 0;
        root = tot = 0;
        newnode(root,0,0);
        newnode(ch[root][1],0,root);
        build(ch[ch[root][1]][0],1,o,ch[root][1]);
        size[root] = 2;
        pushup(ch[root][1]);
        pushup(root);
    }
}SP;
int main()
{
    int n,q;
    while(scanf("%d%d",&n,&q)!=EOF)
    {
        if(n==-1&&q==-1) break;
        SP.init(n);
        while(q--)
        {
            char sq[20];
            int k,x,y;
            scanf("%s",sq);
            if(sq[0]=='C')
            {
                scanf("%d%d%d",&x,&y,&k);
                SP.cut(x,y,k+1);
              // SP.debug();
//                SP.work(n);
            }
            else
            {
                //SP.debug();
                scanf("%d%d",&x,&y);
                SP.filp(x,y);
                //SP.debug();
            }
            //SP.work(n);
        }
        SP.work(n);
    }
    return 0;
}