splay

自顶向下splay

纯手写，没有借鉴他人写法，写得丑也木办法了。

伪代码借鉴http://wenku.baidu.com/view/b9cc2c75a417866fb84a8ee4.html

zkw神犇有漂亮的实现，但是不喜欢指针，所以只能自己yy

纯水：

near

给出N个数，问对于第i(i>=2)个数，从1到i-1中与它最接近的数与它的差是多少。

插入即查询，所以只需一次提根就都完成，速度比一般splay快一倍，比某些递归版treap快。

#include <cstdio>#include <cstdlib>#include <cstring>int n,l[100000],r[100000],id[100000],mid,ll,rr,lr,rl,ss,ans;const int oo=1073741819;int min(int x,int y) {return (x<y) ? x : y;}int right(int x,int y) {l[y]=r[x],r[x]=y;return x;}int left(int x,int y)  {r[y]=l[x],l[x]=y;return x;}void rconnect(int x){if (0==rr) {rl=rr=x;return ;}l[rl]=x,rl=x;}void lconnect(int x){if (0==ll) {lr=ll=x;return ;}r[lr]=x,lr=x;}int ask(int x){  int sum=oo,y;  ll=rr=lr=rl=0;  for (;(id[mid]!=x)&&(mid);)    if (id[mid]>x) {      if ((id[l[mid]]>x)&&(l[mid])) mid=right(l[mid],mid);      rconnect(mid),y=mid,mid=l[mid],l[y]=0;    }    else {      if ((id[r[mid]]<x)&&(r[mid])) mid=left(r[mid],mid);      lconnect(mid),y=mid,mid=r[mid],r[y]=0;    }  if (0==mid) mid=++ss,id[mid]=x;else sum=0;  if (l[mid]) lconnect(l[mid]);  if (r[mid]) rconnect(r[mid]);  l[mid]=ll,r[mid]=rr;  if (lr) sum=min(sum,x-id[lr]);  if (rl) sum=min(sum,id[rl]-x);  return sum;}void init(){  int i,x;  scanf("%d\n",&n);scanf("%d",&x);  id[mid=1]=x,ss=1;  for (i=2;i<=n;i++)  {    scanf("%d",&x);    ans=ask(x);    printf("%d\n",ans);  }}int main(){  freopen("near.in","r",stdin);  freopen("near.out","w",stdout);    init();  return 0;}

poj 3580

题意：http://blog.sina.com.cn/s/blog_6c7729450100uv8k.html

交换区间比较麻烦，参考了http://blog.csdn.net/pouy94/article/details/5751183

需要4次提根

#include <cstdio>#include <cstdlib>#include <cstring>const int maxn=300000,oo=1073741819;int n,m,ans,e,ll,rr,lr,rl,mid,ss;int l[maxn],r[maxn],ls[maxn],rs[maxn],sum[maxn],id[maxn],size[maxn],t[maxn],a[maxn],op[maxn];inline int min(int x,int y) {return (x<y) ? x : y;}inline void swap(int x) {if (0==x) return ;e=l[x],l[x]=r[x],r[x]=e,id[x]=size[l[x]]+1;}inline void pushdown(int x){ if (0==x) return ;  if ((0==t[x])&&(0==op[x])) return ;  if (t[x]) {    if (l[x]) sum[l[x]]+=t[x],a[l[x]]+=t[x],t[l[x]]+=t[x];    if (r[x]) sum[r[x]]+=t[x],a[r[x]]+=t[x],t[r[x]]+=t[x];  }  if (op[x]) swap(l[x]),swap(r[x]),op[l[x]]^=1,op[r[x]]^=1;  t[x]=op[x]=0;}inline void updata(int x)   {if (0==x) return ;size[x]=size[l[x]]+size[r[x]]+1,sum[x]=min(a[x],min(sum[l[x]],sum[r[x]])),id[x]=size[l[x]]+1;}inline int left(int x,int y) {pushdown(x),r[y]=l[x],l[x]=y,updata(y);return x;}inline int right(int x,int y){pushdown(x),l[y]=r[x],r[x]=y,updata(y);return x;}inline void lconnect(int x) {if (0==ll) {ll=lr=x,ls[ls[0]=1]=x;return ;}r[lr]=x,lr=x,ls[++ls[0]]=x;}inline void rconnect(int x) {if (0==rr) {rr=rl=x,rs[rs[0]=1]=x;return ;}l[rl]=x,rl=x,rs[++rs[0]]=x;}inline void splay(int &mid,int x){  int i,y;  ll=rr=lr=rl=rs[0]=ls[0]=0;  for (;x!=(id[mid]-1);) {      pushdown(mid);      if (x>(id[mid]-1)) {  x-=id[mid];          if ((x>(id[r[mid]]-1))&&(r[mid])) x-=id[r[mid]],mid=left(r[mid],mid);          lconnect(mid),y=r[mid],r[mid]=0,mid=y;               }      else {            if ((x<(id[l[mid]]-1))&&(l[mid])) mid=right(l[mid],mid);          rconnect(mid),y=l[mid],l[mid]=0,mid=y;      }  }  pushdown(mid),pushdown(l[mid]),pushdown(r[mid]);  if (l[mid]) lconnect(l[mid]),ls[0]--;  if (r[mid]) rconnect(r[mid]),rs[0]--;  for (i=ls[0];i>=1;i--) updata(ls[i]);  for (i=rs[0];i>=1;i--) updata(rs[i]);  l[mid]=ll,r[mid]=rr,updata(mid);}inline int build(int ll,int rr){  int mid=(ll+rr)>>1;  if (mid+1<=rr) r[mid]=build(mid+1,rr);  if (ll<=mid-1) l[mid]=build(ll,mid-1);  updata(mid);return mid;}void init(){  int i,al,ar,ak,mo,aa,bb,cc,y;  char ch[100];  scanf("%d\n",&n);n+=2;  for (i=2;i<=n-1;i++) scanf("%d\n",&a[i]),sum[i]=a[i],size[i]=1;  size[1]=size[n]=1,sum[1]=sum[n]=oo,a[1]=a[n]=oo;    sum[0]=a[0]=oo,mid=build(1,n);  scanf("%d\n",&m);  for (i=1,ss=n;i<=m;i++)  {    scanf("%s",ch+1);    if ('A'==ch[1]) {        scanf("%d%d%d\n",&al,&ar,&ak);al++,ar++;        splay(mid,ar);        splay(l[mid],al-2);        al=r[l[mid]];        t[al]+=ak,sum[al]+=ak,a[al]+=ak;        updata(l[mid]),updata(mid);    }    else if (('R'==ch[1])&&('E'==ch[4])) {        scanf("%d%d\n",&al,&ar);al++,ar++;        splay(mid,ar);        splay(l[mid],al-2);        al=r[l[mid]];        swap(al),op[al]^=1;    }    else if (('R'==ch[1])&&('O'==ch[4])) {        scanf("%d%d%d\n",&al,&ar,&ak);al++,ar++;        mo=(ar-al+1),ak=(ak+mo)%mo;        aa=al,bb=ar-ak,cc=ar;        if ((bb<aa)||(bb+1>cc)) continue;        splay(mid,bb-1);        splay(l[mid],aa-2);        splay(r[mid],cc-id[mid]);        y=l[mid],l[mid]=r[y],r[y]=l[r[mid]],l[r[mid]]=0;        updata(r[mid]),updata(mid),updata(y);        splay(mid,0);       //splay(y,cc-);        l[mid]=y;updata(mid);    }    else if ('I'==ch[1]) {        scanf("%d%d\n",&al,&ak);al++;        splay(mid,al);        splay(l[mid],al-1);        r[l[mid]]=++ss;        sum[ss]=a[ss]=ak,size[ss]=1,id[ss]=1;        updata(l[mid]),updata(mid);    }    else if ('D'==ch[1]) {        scanf("%d%d\n",&al);al++;        splay(mid,al);        splay(l[mid],al-2);        r[l[mid]]=0;        updata(l[mid]),updata(mid);    }    else if ('M'==ch[1]) {        scanf("%d%d\n",&al,&ar);al++,ar++;        splay(mid,ar);        splay(l[mid],al-2);        ans=sum[r[l[mid]]];        printf("%d\n",ans);    }  }}int main(){  freopen("3580.in","r",stdin);  freopen("3580.out","w",stdout);    init();  return 0;}