【bz2002】弹飞绵羊

题意：

给出n个节点 及其父亲 和m个指令1：表示求节点i到根节点（n+1）的距离2：表示将节点i的父亲更换为j

题解：

动态树link、cut、access模板题 貌似没什么难度- -

代码：

 #include <cstdio>
 struct info{
        int fat,root,lc,rc,num;
        info(const int a=,const int b=,const int c=,const int d=,const int e=):
                   fat(a),root(b),lc(c),rc(d),num(e){}
 };
 int n,m;
 info tree[];
 void clean(){
      tree[]=info(,,,,);
 }
 void makenum(int t){
      tree[t].num=+tree[tree[t].lc].num+tree[tree[t].rc].num;
 }
 void left(int t){
      int fa=tree[t].fat,r=tree[t].rc;
      tree[t].rc=tree[r].lc;
      tree[tree[r].lc].fat=t;
      tree[r].lc=t;
      tree[t].fat=r;
      if (tree[t].root){
                        tree[t].root=;
                        tree[r].root=;
      }else if (tree[fa].lc==t) tree[fa].lc=r;
      else tree[fa].rc=r;
      tree[r].fat=fa;
      clean();
      makenum(t);
      makenum(r);
 }
 void right(int t){
      int fa=tree[t].fat,l=tree[t].lc;
      tree[t].lc=tree[l].rc;
      tree[tree[l].rc].fat=t;
      tree[l].rc=t;
      tree[t].fat=l;
      if (tree[t].root){
                        tree[t].root=;
                        tree[l].root=;
      }else if (tree[fa].lc==t) tree[fa].lc=l;
            else tree[fa].rc=l;
      tree[l].fat=fa;
      clean();
      makenum(t);
      makenum(l);
 }
 void splay(int t){
      while (!tree[t].root){
            int fa=tree[t].fat,gr=tree[fa].fat;
            if (tree[fa].root){
                               if (tree[fa].lc==t) right(fa);
                               else left(fa);
            }else if (tree[gr].lc==fa){
                     if (tree[fa].lc==t) right(gr),right(fa);
                     else left(fa),right(gr);
                  }else if (tree[fa].rc==t) left(gr),left(fa);
                        else right(fa),left(gr);
      }
 }
 void access(int x){
      int y=x;
      x=;
      do{
          splay(y);
          tree[tree[y].rc].root=;
          tree[y].rc=x;
          tree[x].root=;
          clean();
          makenum(y);
          x=y;
          y=tree[x].fat;
      }while (y);
 }
 void change(int x,int y){
      access(x);
      splay(x);
      tree[tree[x].lc].fat=;
      tree[tree[x].lc].root=;
      tree[x].lc=;
      tree[x].fat=y;
      clean();
      access(x);
 }
 int main(){
     freopen("bz2002.in","r",stdin);
     freopen("bz2002.out","w",stdout);
     int i,x,y,z;
     scanf("%d\n",&n);
     for (i=;i<=n;i++){
         scanf("%d",&x);
         x+=i;
         if (x<=n) tree[i].fat=x;
         else tree[i].fat=n+;
     }
     scanf("%d\n",&m);
     for (i=;i<=m;i++){
         scanf("%d%d",&x,&y);
         ++y;
         if (x==){
                   scanf("%d",&z);
                   change(y,y+z);
         }else{
               access(y);
               splay(y);
               printf("%d\n",tree[tree[y].lc].num);
         }
     }
     fclose(stdin);
     fclose(stdout);
 }