模板：
1 #include<iostream> 2 #include<cstdio> 3 #include<cstring> 4 #include<cmath> 5 using namespace std; 6 #define R register 7 #define ll long long 8 inline ll read(){ 9 ll aa=0;R int bb=1;char cc=getchar(); 10 while(cc<'0'||cc>'9') 11 {if(cc=='-')bb=-1;cc=getchar();} 12 while(cc>='0'&&cc<='9') 13 {aa=(aa<<1)+(aa<<3)+(cc^48);cc=getchar();} 14 return aa*bb; 15 } 16 const int N=1e5+3; 17 struct edge{ 18 int v,last; 19 }ed[N<<1]; 20 int first[N],tot; 21 inline void add(int x,int y) 22 { 23 ed[++tot].v=y; 24 ed[tot].last=first[x]; 25 first[x]=tot; 26 } 27 int n,m,c[N],son[N],cnt[N],ans[N],siz[N]; 28 void dfsi(int x,int fa) 29 { 30 siz[x]=1; 31 for(R int i=first[x],v;i;i=ed[i].last){ 32 v=ed[i].v; 33 if(v==fa)continue; 34 dfsi(v,x); 35 siz[x]+=siz[v]; 36 if(siz[v]>siz[son[x]])son[x]=v; 37 } 38 return; 39 } 40 int dfsj(int x,int fa,int bs,int kep) 41 { 42 if(kep){ 43 for(R int i=first[x],v;i;i=ed[i].last){ 44 v=ed[i].v; 45 if(v!=fa&&v!=son[x]) 46 dfsj(v,x,0,1); 47 } 48 } 49 int res=0; 50 if(son[x])res+=dfsj(son[x],x,1,kep); 51 for(R int i=first[x],v;i;i=ed[i].last){ 52 v=ed[i].v; 53 if(v!=fa&&v!=son[x]) 54 res+=dfsj(v,x,0,0); 55 } 56 if(!cnt[c[x]])res++; 57 cnt[c[x]]++; 58 if(kep){ 59 ans[x]=res; 60 if(!bs)memset(cnt,0,sizeof(cnt)); 61 } 62 return res; 63 } 64 int main() 65 { 66 n=read(); 67 for(R int i=1,x,y;i<n;++i){ 68 x=read();y=read(); 69 add(x,y);add(y,x); 70 } 71 for(R int i=1;i<=n;++i)c[i]=read(); 72 dfsi(1,0); dfsj(1,0,1,1); 73 m=read(); 74 for(R int i=1,x;i<=m;++i){ 75 x=read(); 76 printf("%d ",ans[x]); 77 } 78 return 0; 79 }
1 // luogu-judger-enable-o2 2 #include<bits/stdc++.h> 3 using namespace std; 4 #define ll int 5 #define r register 6 #define A 1001010 7 ll head[A],nxt[A],ver[A],size[A],col[A],cnt[A],ans[A],son[A]; 8 ll tot=0,num,sum,nowson,n,m,xx,yy; 9 inline void add(ll x,ll y){ 10 nxt[++tot]=head[x],head[x]=tot,ver[tot]=y; 11 } 12 inline ll read(){ 13 ll f=1,x=0;char c=getchar(); 14 while(!isdigit(c)){ 15 if(c=='-') f=-1; 16 c=getchar(); 17 } 18 while(isdigit(c)) 19 x=(x<<1)+(x<<3)+(c^48),c=getchar(); 20 return f*x; 21 } 22 void dfs(ll x,ll fa){ 23 size[x]=1; 24 for(ll i=head[x];i;i=nxt[i]){ 25 ll y=ver[i]; 26 if(y==fa) continue; 27 dfs(y,x); 28 size[x]+=size[y]; 29 if(size[son[x]]<size[y]) 30 son[x]=y; 31 } 32 } 33 void cal(ll x,ll fa,ll val){ 34 if(!cnt[col[x]]) ++sum; 35 cnt[col[x]]+=val; 36 for(ll i=head[x];i;i=nxt[i]){ 37 ll y=ver[i]; 38 if(y==fa||y==nowson) continue; 39 cal(y,x,val); 40 } 41 } 42 void dsu(ll x,ll fa,bool op){ 43 for(ll i=head[x];i;i=nxt[i]){ 44 ll y=ver[i]; 45 if(y==fa||y==son[x]) 46 continue; 47 dsu(y,x,0); 48 //从轻儿子出发 49 } 50 if(son[x]) 51 dsu(son[x],x,1),nowson=son[x]; 52 cal(x,fa,1);nowson=0; 53 ans[x]=sum; 54 if(!op){ 55 cal(x,fa,-1); 56 sum=0; 57 } 58 } 59 int main(){ 60 n=read(); 61 for(ll i=1;i<=n-1;i++){ 62 xx=read(),yy=read(); 63 add(xx,yy),add(yy,xx); 64 } 65 for(ll i=1;i<=n;i++) 66 col[i]=read(); 67 dfs(1,0); 68 dsu(1,0,1); 69 m=read(); 70 for(ll i=1;i<=m;i++){ 71 xx=read(); 72 printf("%d ",ans[xx]); 73 } 74 }