hdu4453 伸展树

第一道伸展树题目  7K的代码连写带调耗了将近一天时间 各种细节错误 AC的时候有种解脱的感觉 终于不用睡不着觉了 数据结构的题目就是坑

#include<set>
#include<map>
#include<cmath>
#include<vector>
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
typedef long long LL;

const int NS=200100;
const double eps=1e-8;

int n,m,k1,k2,pos,cnt;
int arr[NS];

int deg=0;
#define debug if(deg)
#define debuv debug{spt.traval(spt.root);}

struct splaytree{
#define ls(cur) ch[cur][0]
#define rs(cur) ch[cur][1]
int root;
int sz[NS],fp[NS];
int key[NS],val[NS];
int ch[NS][2],pre[NS];

void Pushdown(int x)
{
if (!val[x] && !fp[x]) return ;
int l=ls(x),r=rs(x);
if (l>0)
key[l]+=val[x],val[l]+=val[x],fp[l]^=fp[x];
if (r>0)
key[r]+=val[x],val[r]+=val[x],fp[r]^=fp[x];
if (fp[x]) swap(ls(x),rs(x));
val[x]=fp[x]=0;
}

void Pushup(int x)
{
sz[x]=sz[ls(x)]+sz[rs(x)]+1;
}

void Rotate(int x,int dir) //0右旋 1左旋
{
int y=pre[x],z=pre[y];
Pushdown(y),Pushdown(x);
pre[x]=z,pre[y]=x;
if (z>0)
if (ch[z][0]==y)
ch[z][0]=x;
else
ch[z][1]=x;
z=ch[y][dir]=ch[x][!dir];
if (z>0) pre[z]=y;
ch[x][!dir]=y;
if (y==root) root=x;
Pushup(y);
}

void splay(int x,int fa)
{
for (;pre[x]!=fa;)
{
int y=pre[x],z=pre[y];
if (z==fa)
if (ch[y][0]==x)
Rotate(x,0);
else
Rotate(x,1);
else
if (ch[z][0]==y)
if (ch[y][0]==x)
Rotate(y,0),Rotate(x,0);
else
Rotate(x,1),Rotate(x,0);
else
if (ch[y][0]==x)
Rotate(x,0),Rotate(x,1);
else
Rotate(y,1),Rotate(x,1);
}
Pushup(x);
}

int findkth(int x,int k)
{
Pushdown(x);
for(int i=sz[ls(x)];i+1!=k;i=sz[ls(x)])
{
if (i>=k)
x=ls(x);
else
k-=i+1,x=rs(x);
Pushdown(x);
}
return x;
}

int newnode(int x,int v)
{
key[cnt]=v,sz[cnt]=1;
val[cnt]=fp[cnt]=0;
ls(cnt)=rs(cnt)=0;
pre[cnt]=x;
return cnt++;
}

void change()
{
if (sz[root]<=2) pos=1;
else if (pos>=sz[root]) pos=2;
else if (pos<2) pos=sz[root]-1;
}

void init(int n)
{
for (int i=0;i<3;i++)
pre[i]=val[i]=key[i]=sz[i]=fp[i]=ls(i)=rs(i)=0;
pos=root=2,cnt=n+4;
int fa=0;
for (int i=2;i<n+3;i++)
{
val[i]=fp[i]=ls(i)=0;
pre[i]=fa; fa=i;
key[i]=arr[i]; sz[i]=cnt-i;
rs(i)=i+1;
}
rs(fa)=sz[1]=1,pre[1]=fa;
}

void add(int st,int v)
{
int tot=sz[root]-2;
if (tot<=0) return ;
val[root]+=k2/tot*v;
key[root]+=k2/tot*v;
int num=k2%tot;
if (!num) return ;
tot=sz[root];
if (st>2)
{
splay(findkth(root,1),0);
splay(findkth(root,st),root);
int trt=ls(rs(root));
pre[trt]=ls(rs(root))=0;
Pushup(rs(root)); Pushup(root);

splay(findkth(root,tot-st+2),0);
splay(findkth(root,tot-st+1),root);
rs(ls(root))=trt; pre[trt]=ls(root);
Pushup(ls(root)); Pushup(root);
pos=2;
}
splay(findkth(root,1),0);
splay(findkth(rs(root),num+1),root);
val[ls(rs(root))]+=v;
key[ls(rs(root))]+=v;
}

void reverse(int st)
{
int tot=sz[root];
if (tot<=2) return ;
if (st>2)
{
splay(findkth(root,1),0);
splay(findkth(root,st),root);
int trt=ls(rs(root));
pre[trt]=ls(rs(root))=0;
Pushup(rs(root)); Pushup(root);

splay(findkth(root,tot-st+2),0);
splay(findkth(root,tot-st+1),root);
rs(ls(root))=trt; pre[trt]=ls(root);
Pushup(ls(root)); Pushup(root);
pos=2;
}
splay(findkth(root,1),0);
splay(findkth(rs(root),k1+1),root);
if (ls(rs(root)))
fp[ls(rs(root))]^=1;
}

void insert(int st,int v)
{
splay(findkth(root,st),0);
splay(findkth(rs(root),1),root);
ls(rs(root))=newnode(rs(root),v);
Pushup(rs(root)),Pushup(root);
change();
}

void Delete(int st)
{
splay(findkth(root,st-1),0);
splay(findkth(rs(root),2),root);
ls(rs(root))=0;
Pushup(rs(root)),Pushup(root);
change();
}

void move(int x)
{
pos+= x==1?-1:1;
change();
}

int query(int st)
{
splay(findkth(root,st),0);
return key[root];
}

void traval(int x)
{
if (!deg) return ;
printf("rt=%d  cur=%d\n",root,key[x]);
visit(x);
}

void visit(int x)
{
Pushdown(x);
int l=ch[x][0],r=ch[x][1];
if (l>0) visit(l);
printf("pos=%d fa=%d key=%d val=%d fp=%d sz=%d l=%d r=%d\n",
x,pre[x],key[x],val[x],fp[x],sz[x],key[ls(x)],key[rs(x)]);
if (r>0) visit(r);
Pushup(x);
}
}spt;

int main()
{
int cas=0;
while (~scanf("%d %d %d %d",&n,&m,&k1,&k2))
{
if (n+m+k1+k2==0) break;
printf("Case #%d:\n",++cas);
for (int i=3;i<n+3;i++)
scanf("%d",&arr[i]);
arr[1]=arr[2]=0;
spt.init(n);
char op[10];
for (int x;m--;)
{
scanf("%s",op);
if (op[0]=='a')
{
scanf("%d",&x);
spt.add(pos,x);
}else
if (op[0]=='r')
{
spt.reverse(pos);
}else
if (op[0]=='i')
{
scanf("%d",&x);
spt.insert(pos,x);
}else
if (op[0]=='d')
{
spt.Delete(pos);
}else
if (op[0]=='m')
{
scanf("%d",&x);
spt.move(x);
}else
if (op[0]=='q')
{
printf("%d\n",spt.query(pos));
}
}
}
return 0;
}