【BZOJ】【2002】【HNOI2010】弹飞绵羊

  1 /**************************************************************
  2     Problem: 2002
  3     User: Tunix
  4     Language: C++
  5     Result: Accepted
  6     Time:1932 ms
  7     Memory:6156 kb
  8 ****************************************************************/
  9  
 10 //BZOJ 2002
 11 #include<cstdio>
 12 #include<cstdlib>
 13 #include<cstring>
 14 #include<iostream>
 15 #include<algorithm>
 16 #define rep(i,n) for(int i=0;i<n;++i)
 17 #define F(i,j,n) for(int i=j;i<=n;++i)
 18 #define D(i,j,n) for(int i=j;i>=n;--i)
 19 using namespace std;
 20 const int N=200010;
 21  
 22 int c[N][2],fa[N],size[N],n,m,k[N],st[N],top=0;
 23 bool rev[N];
 24  
 25 int read(){
 26     char ch=getchar();
 27     int sig=1,tmp=0;
 28     while(ch<‘0‘||ch>‘9‘) {if (ch==‘-‘) sig=-1;ch=getchar();}
 29     while(ch>=‘0‘ && ch<=‘9‘) {tmp=10*tmp+ch-‘0‘;ch=getchar();}
 30     return tmp*sig;
 31 }
 32  
 33 void Push_down(int x){
 34     if (rev[x]){
 35         rev[x]^=1; rev[c[x][0]]^=1; rev[c[x][1]]^=1;
 36         swap(c[x][0],c[x][1]);
 37     }
 38 }
 39 inline void Push_up(int x){
 40     size[x]=size[c[x][0]]+size[c[x][1]]+1;
 41 }
 42 bool isroot(int x){
 43     return c[fa[x]][0]!=x && c[fa[x]][1]!=x;
 44 }
 45 void rotate(int x){
 46     int y=fa[x],z=fa[y],l=c[y][1]==x,r=l^1;
 47     if (!isroot(y)) c[z][c[z][1]==y]=x;
 48     fa[x]=z; fa[y]=x; fa[c[x][r]]=y;
 49     c[y][l]=c[x][r]; c[x][r]=y;
 50     Push_up(y); Push_up(x);
 51 }
 52 void splay(int x){
 53     top=0; st[top++]=x;
 54     for(int i=x;!isroot(i);i=fa[i])
 55         st[top++]=fa[i];
 56     while(top--) Push_down(st[top]);
 57      
 58     while(!isroot(x)){
 59         int y=fa[x],z=fa[y];
 60         if (!isroot(y)){
 61             if (c[y][0]==x^c[z][0]==y) rotate(x);
 62             else rotate(y);
 63         }
 64         rotate(x);
 65     }
 66 }
 67 void access(int x){
 68     for(int t=0;x;t=x,x=fa[x])
 69         splay(x),c[x][1]=t,Push_up(x);
 70 }
 71 void makeroot(int x){
 72     access(x); splay(x); rev[x]^=1;
 73 }
 74 int find(int x){
 75     access(x); splay(x);
 76     while(c[x][0]) x=c[x][0];
 77     return x;
 78 }
 79 void cut(int x,int y){
 80     makeroot(x); access(y); splay(y);
 81     if (c[y][0]==x) c[y][0]=fa[x]=0;
 82 }
 83 void link(int x,int y){
 84     makeroot(x); fa[x]=y;
 85 }
 86 //LCT end
 87 int main(){
 88 //  freopen("input.txt","r",stdin);
 89     n=read();
 90     F(i,1,n){
 91         k[i]=read();
 92         link(i,min(i+k[i],n+1));
 93     }
 94     m=read();
 95     int x,y,z;
 96     F(i,1,m){
 97         x=read(); y=read(); y++;
 98         if (x==1) {
 99             makeroot(n+1);
100             access(y);splay(y);
101             printf("%d\n",size[y]-1);
102         }
103         else if(x==2){
104             z=read();
105             cut(y,min(y+k[y],n+1));
106             k[y]=z;
107             link(y,min(y+k[y],n+1));
108         }
109     }      
110     return 0;
111 }