bzoj 4923 K小值查询（Splay）

题目链接:http://www.lydsy.com/JudgeOnline/problem.php?id=4923

解法题解里说的挺清楚的，好吧，我就是找个地方存一哈代码...

辣鸡卡常题，跑了16s竟然判过了....实在是优化不动了

代码：

#include<bits/stdc++.h>using namespace std;const int MAXN=100010;const int INF=2e9+5;int a[MAXN];int n,q;namespace Splay_Tree{#define Key_value ch[ch[root][1]][0] int pre[MAXN],ch[MAXN][2],key[MAXN],size[MAXN],sub[MAXN],tmp[MAXN];int root,tot1,cnt;inline void NewNode(int &r,int father,int k){r=++tot1;pre[r]=father;ch[r][0]=ch[r][1]=0;key[r]=k;size[r]=1;sub[r]=0;}inline void push_up(int r){int lson=ch[r][0],rson=ch[r][1];size[r]=size[lson]+size[rson]+1;}inline void up_sub(int r,int k){if(!r)return ;if(key[r]!=-1&&key[r]!=INF)key[r]-=k;sub[r]+=k;}inline void push_down(int r){if(sub[r]){up_sub(ch[r][0],sub[r]);up_sub(ch[r][1],sub[r]);sub[r]=0;}}inline void Build(int &x,int l,int r,int father){if(l>r)return;int mid=(l+r)/2;NewNode(x,father,a[mid]);Build(ch[x][0],l,mid-1,x);Build(ch[x][1],mid+1,r,x);push_up(x);}inline void Init(){root=tot1=0;ch[root][0]=ch[root][1]=size[root]=pre[root]=0;key[root]=0;sub[root]=0;NewNode(root,0,-1);NewNode(ch[root][1],root,INF);Build(Key_value,1,n,ch[root][1]);push_up(ch[root][1]);push_up(root);}//旋转,0为左旋，1为右旋 inline void Rotate(int x,int kind){int y=pre[x];push_down(y);push_down(x);ch[y][!kind]=ch[x][kind];pre[ch[x][kind]]=y;if(pre[y])ch[pre[y]][ch[pre[y]][1]==y]=x;pre[x]=pre[y];ch[x][kind]=y;pre[y]=x;push_up(y);}//Splay调整，将r结点调整到goal下面 inline void Splay(int r,int goal){push_down(r);while(pre[r]!=goal){if(pre[pre[r]]==goal){push_down(pre[r]);push_down(r);Rotate(r,ch[pre[r]][0]==r);}else{push_down(pre[pre[r]]);push_down(pre[r]);push_down(r);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);}}}push_up(r);if(goal==0)root=r;}//获得第K个位置数inline int Get_kth(int r,int k){push_down(r);int t=size[ch[r][0]]+1;if(t==k)return r;if(t>k)return Get_kth(ch[r][0],k);elsereturn Get_kth(ch[r][1],k-t);}inline int Get_mx(int r){push_down(r);if(ch[r][1])return Get_mx(ch[r][1]);return r;}inline int Get_mi(int r){push_down(r);if(ch[r][0])return Get_mx(ch[r][0]);return r;}inline int Get_ri(int r,int k){int ret=-1;while(1){push_down(r);if(key[r]>k){ret=r;if(ch[r][0])r=ch[r][0];elsereturn ret;}else{if(ch[r][1])r=ch[r][1];elsereturn ret;}}}inline int Get_lf(int r,int k){int ret=-1;while(1){push_down(r);if(key[r]<=k){ret=r;if(ch[r][1])r=ch[r][1];elsereturn ret;}else{if(ch[r][0])r=ch[r][0];elsereturn ret;}}}inline void InOrder(int r){if(!r)return;push_down(r);InOrder(ch[r][0]);tmp[cnt++]=r;InOrder(ch[r][1]);}inline int Get_next(int r){    push_down(r);    if(ch[r][1]==0)return -1;    r=ch[r][1];push_down(r);    while(ch[r][0])    {        r=ch[r][0];        push_down(r);    }    return r;}void Insert(int r,int now){push_down(r);if(key[tmp[now]]<key[r]){if(ch[r][0]){Insert(ch[r][0],now);}else{pre[tmp[now]]=r;ch[r][0]=tmp[now];ch[tmp[now]][0]=ch[tmp[now]][1]=0;size[tmp[now]]=1;sub[tmp[now]]=0;}push_up(r);}if(key[tmp[now]]>=key[r]){if(ch[r][1]){Insert(ch[r][1],now);}else{pre[tmp[now]]=r;ch[r][1]=tmp[now];ch[tmp[now]][0]=ch[tmp[now]][1]=0;size[tmp[now]]=1;sub[tmp[now]]=0;}push_up(r);}}void change(int k){int l=Get_lf(root,k);Splay(l,0);int r=Get_ri(root,k+k);Splay(r,root);if(key[ch[root][1]]!=INF){key[ch[root][1]]-=k;}sub[ch[root][1]]+=k;push_down(ch[root][1]);if(Key_value==0)return ;int sv=Key_value;cnt=0;pre[sv]=0;Key_value=0;InOrder(sv);int now=0;while(now<cnt)Insert(root,now++);}}using namespace Splay_Tree;inline char nc(){  static char buf[100000],*p1=buf,*p2=buf;  return p1==p2&&(p2=(p1=buf)+fread(buf,1,100000,stdin),p1==p2)?EOF:*p1++;}inline void rea(int &x){  char c=nc(); x=0;  for(;c>'9'||c<'0';c=nc());for(;c>='0'&&c<='9';x=x*10+c-'0',c=nc());}int op,k;int main(){//freopen("in.in","r",stdin);//freopen("out.out","w",stdout);rea(n);rea(q);for(int i=1;i<=n;i++){rea(a[i]);}sort(a+1,a+1+n);Init();Splay(1,0);while(q--){rea(op);rea(k);if(op==1){printf("%d\n",key[Get_kth(root,k+1)]);}else{change(k);}}return 0;}