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 ;

 }