P3258 [JLOI2014]松鼠的新家

P3258 [JLOI2014]松鼠的新家
倍增lca+树上差分，从叶子节点向根节点求前缀和，dfs求子树和即可，最后，把每次的起点和终点都。

 #include<iostream>
 #include<cstdio>
 #include<queue>
 #include<algorithm>
 #include<cmath>
 #include<ctime>
 #include<set>
 #include<map>
 #include<stack>
 #include<cstring>
 #define inf 2147483647
 #define For(i,a,b) for(register int i=a;i<=b;i++)
 #define p(a) putchar(a)
 #define g() getchar()
 //by war
 //2017.11.8
 using namespace std;
 int f[][];
 int a[],b[];
 int deep[];
 int change[];
 bool vis[];
 int lca;
 int x,y;
 int n;
 struct node
 {
     int n;
     node *next;
 }*e[];

 inline void in(register int &x)
 {
     int y=;
     char c=g();x=;
     while(c<''||c>'')
     {
     if(c=='-')
     y=-;
     c=g();
     }
     while(c<=''&&c>='')x=(x<<)+(x<<)+c-'',c=g();
     x*=y;
 }
 inline void o(register int x)
 {
     if(x<)
     {
         p('-');
         x=-x;
     }
     if(x>)o(x/);
     p(x%+'');
 }

 inline void push(register int x,register int y)
 {
     node *p;
     p=new node();
     p->n=y;
     if(e[x]==NULL)
     e[x]=p;
     else
     {
         p->next=e[x]->next;
         e[x]->next=p;
     }
 }

 inline void build(register int now)
 {
     deep[now]=deep[f[now][]]+;
     for(register int i=;(<<i)<=n;i++)
     f[now][i]=f[f[now][i-]][i-];
     for(node *i=e[now];i!=NULL;i=i->next)
     {
         if(f[now][]!=i->n)
         {
             f[i->n][]=now;
             build(i->n);
         }
     }
 }

 inline int query(register int x,register int y)
 {
     if(deep[x]<deep[y])
     swap(x,y);
     int c=deep[x]-deep[y];
     for(register int i=;(<<i)<=c;i++)
     if((<<i)&c)
     x=f[x][i];
     if(x==y)
     return x;
     for(register int i=log2(deep[x]);i>=;i--)
     {
         if(f[x][i]!=f[y][i])
         {
             x=f[x][i];
             y=f[y][i];
         }
     }
     return f[x][];
 }

 int dfs(int now)
 {
     if(vis[now])
     return b[now];
     vis[now]=true;
     for(node *i=e[now];i!=NULL;i=i->next)
     if(!vis[i->n])
     {
     x=dfs(i->n);
     b[now]+=x;
     }
     return b[now];
 }

 int main()
 {
 //    freopen("t.in","r",stdin);
 //    freopen("t2.out","w",stdout);
     in(n);
     For(i,,n)
     in(a[i]);
     For(i,,n-)
     {
         in(x),in(y);
         push(x,y);
         push(y,x);
     }
 //    f[0][0]=0;
     build();
     For(i,,n-)
     {
         x=a[i];
         y=a[i+];
         lca=query(x,y);
         change[x]++;
         change[y]++;
         change[lca]--;
         change[f[lca][]]--;
     }
     For(i,,n)
     b[i]=change[i];
     b[]=dfs();
     For(i,,n)
     b[a[i]]--;
     For(i,,n)
     o(b[i]),p('\n');
      return ;
 }