Bzoj 2002: [hnoi2010] bounce Bullet Flying sheep LCT

LCT maintains the subtree size .....

2002: [hnoi2010] bounce time limit: 10 sec memory limit: 259 MB
Submit: 4085 solved: 2188
[Submit] [Status] Description

One day, lostmonkey invented a super elastic device. He invited little sheep to play a game in order to show it in front of his friends. At the beginning of the game, lostmonkey placed n devices along a straight line on the ground, each of which sets the initial elasticity factor Ki. When the sheep reach the I device, it will play the ki step back, reaches the I + Ki device. If the I + Ki device does not exist, the sheep will fly. The sheep wanted to know that when it started from the I device, it would fly after several rounds. To make the game more interesting, lostmonkey can modify the elasticity coefficient of a certain stretch device. The elasticity coefficient is a positive integer at any time.

Input

The first line contains an integer N, indicating that there are n devices on the ground. The device number ranges from 0 to n-1, And the next line contains n positive integers, the initial elasticity coefficient of the N devices in turn. The third row has a positive integer m, and the next row of M has at least two numbers I and J. If I = 1, you need to output the data to be played several times from J and then fly, if I = 2, a positive integer k is input, indicating that the coefficient of the J-step elastic device is changed to K. For 20% of Data n, m <= 10000, for 100% of Data n <= 200000, m <= 100000

Output

For each I = 1, you need to output a required number of steps, occupying one row.

Sample input4
1 2 1 1
3
1 1
2 1 1
1 1
Sample output2
3
Hint

Source

Splay heuristic merge

[Submit] [Status] Bytes

#include <iostream>#include <cstdio>#include <cstring>#include <algorithm>using namespace std;const int maxn=220000;int n,m;int pre[maxn],ch[maxn][2],size[maxn];bool rt[maxn];void init(){  for(int i=0;i<=n+10;i++)    rt[i]=1,pre[i]=0,ch[i][0]=ch[i][1]=0,size[i]=1;  size[0]=0;}void push_up(int r){  size[r]=size[ch[r][0]]+size[ch[r][1]]+1;}void Rotate(int x){  int y=pre[x],kind=ch[y][1]==x;  ch[y][kind]=ch[x][!kind];  pre[ch[y][kind]]=y;  pre[x]=pre[y];  pre[y]=x;  ch[x][!kind]=y;  if(rt[y]) rt[y]=false,rt[x]=true;  else ch[pre[x]][ch[pre[x]][1]==y]=x;  push_up(y);}void Splay(int r){  while(!rt[r])    {      int f=pre[r],ff=pre[f];      if(rt[f]) Rotate(r);      else if((ch[ff][1]==f)==(ch[f][1]==r)) Rotate(f),Rotate(r);      else Rotate(r),Rotate(r);    }  push_up(r);}int Access(int x){  int y=0;  for(;x;x=pre[y=x])    {      Splay(x);      rt[ch[x][1]]=true; rt[ch[x][1]=y]=false;      push_up(x);    }  return y;}int main(){  while(scanf("%d",&n)!=EOF)    {      init();      for(int i=1;i<=n;i++)        {          int t;          scanf("%d",&t);          pre[i]=(i+t>n+1)?n+1:i+t;        }      scanf("%d",&m);      while(m--)        {          int tk,u,v;          scanf("%d",&tk);          if(tk==1)            {              scanf("%d",&u);              u++;              Access(u);              Splay(u);              printf("%d\n",size[ch[u][0]]);            }          else            {              scanf("%d%d",&u,&v);              u++;              Access(u);              Splay(u);              pre[ch[u][0]]=pre[u];              pre[u]=0;              rt[ch[u][0]]=true;              ch[u][0]=0;              push_up(u);              pre[u]=(u+v)>n+1?n+1:u+v;            }        }    }  return 0;}

Bzoj 2002: [hnoi2010] bounce Bullet Flying sheep LCT