面向数据发现答案略大……从十分调到80实在不知道哪里错了 求助/kel

大概是二分一个时间之后每个军队倍增跳到第二层节点然后把可以继续往其他节点的点给提出来，贪心解决没有被覆盖的点

#include<bits/stdc++.h>
using namespace std;
#define int long long
const int N=3e5+10;
int n,m,f[N][20],s[N][20],Vis[N],sum[N],vp[N];
vector<int>G[N],V[N],Leaf;
int pos[N],cpos[N],dfn[N],idfn[N];
int dfstime,tr[N],ctm[N],siz[N],vis[N];
int anc[N];
vector<int>Tp[N];
inline int read(){
	int s=0,w=1;
	char ch=getchar();
	while(!isdigit(ch)){
		if(ch=='-')w=-1;
		ch=getchar();
	}
	while(isdigit(ch)){
		s=s*10+ch-'0';
		ch=getchar();
	}
	return s*w;
}
inline bool cmp(int x,int y){return x>y;}
void link(int u,int v,int w){
	G[u].push_back(v);
	G[v].push_back(u);
	V[u].push_back(w);
	V[v].push_back(w);
}
void dfs(int x,int fa,int w){
	f[x][0]=fa;s[x][0]=w;
	for(int i=1;i<20;++i)f[x][i]=f[f[x][i-1]][i-1];
	for(int i=1;i<20;++i)s[x][i]=s[x][i-1]+s[f[x][i-1]][i-1];
	idfn[dfn[x]=++dfstime]=x;siz[x]=1;
	for(int i=0;i<(int)G[x].size();++i){
		int v=G[x][i];
		int w=V[x][i];
		if(v==fa)continue;
		dfs(v,x,w);siz[x]+=siz[v];
	}
}
bool check(int Time){
//	printf("Time:%lld:\n",Time);
	multiset<int>S;
	vector<int>U;
	for(int i=1;i<=n+1;++i)vis[i]=Vis[i]=sum[i]=vp[i]=0,Tp[i].clear();
	for(int i=1;i<=m;++i)cpos[i]=pos[i],ctm[i]=0;
	for(int i=1;i<=m;++i)
		for(int j=19;~j;--j)
			if(f[cpos[i]][j]&&ctm[i]+s[cpos[i]][j]<=Time&&f[f[cpos[i]][j]][0]>=1)ctm[i]+=s[cpos[i]][j],cpos[i]=f[cpos[i]][j];
//	for(int i=1;i<=m;++i)cout<<cpos[i]<<" "<<ctm[i]<<endl;
//	puts("Resttime:");
	for(int i=1;i<=m;++i){
		if(f[cpos[i]][0]!=1)continue;
		int Tm=Time-ctm[i]-s[cpos[i]][0];
//		cout<<Tm<<" ";
		Tp[cpos[i]].push_back(Tm);
	}
	for(int i=1;i<=m;++i){
		if(f[cpos[i]][0]!=1)continue;
		vp[cpos[i]]=1;
		if(vis[cpos[i]])continue;
		vis[cpos[i]]=1;
		sort(Tp[cpos[i]].begin(),Tp[cpos[i]].end(),cmp);
	}
	for(int i=1;i<=n+1;++i)vis[i]=0;
	for(int i=1;i<=m;++i){
		if(f[cpos[i]][0]==1)continue;
		int l=dfn[cpos[i]];
		int r=dfn[cpos[i]]+siz[cpos[i]]-1;
		vis[l]++;
		vis[r+1]--;
	}
	for(int i=1;i<=n+1;++i)vis[i]+=vis[i-1];
	for(int i=1;i<=n;++i)if(vis[i])sum[i]=1;
	for(int i=1;i<=n;++i)sum[i]+=sum[i-1];
//	puts("");
//	for(int i=1;i<=n;++i)cout<<vis[i]<<" ";
//	cout<<endl;
//	puts("Anc:");
	for(auto v:Leaf){
//		if(!vis[dfn[v]])cout<<anc[v]<<endl;
		if(!vis[dfn[v]]){
			if(Vis[anc[v]])continue;
			if(vp[anc[v]]==1){
				vp[anc[v]]=2;
				Tp[anc[v]].pop_back();
				continue;
			}
			if(vp[anc[v]]==2)continue;
			S.insert(s[anc[v]][0]);
			Vis[anc[v]]=1;
		}
	}
//	puts("SET:");
//	for(auto v:S)cout<<v<<endl;
	if(S.empty())return true;
	for(int i=1;i<=m;++i){
		if(f[cpos[i]][0]!=1)continue;
		int Siz=(int)Tp[cpos[i]].size();
		for(int ts=0;ts<Siz;++ts){
			int bk=Tp[cpos[i]].back();
//			if(bk<=0)break;
			Tp[cpos[i]].pop_back();
			U.push_back(bk);
		}
	}
	if(U.empty())return false;
	sort(U.begin(),U.end());
//	puts("U:");
//	for(auto v:U)cout<<v<<endl;
//	puts("Deal:");
	int posb=0,SU=(int)U.size();
	while(!S.empty()&&posb<SU){
		int v=*S.begin();
//		int cost=s[v][0];
//		cout<<cost<<endl;
//		cout<<v<<endl;
		while(posb<SU&&U[posb]<v)++posb;
		if(posb==SU)return false;
		posb++;
		multiset<int>::iterator it=S.find(v);
		S.erase(it);
	}
//	puts("SET:");
//	for(auto v:S)cout<<v<<endl;
//	puts("End.");
	return S.empty();
}
signed main(){
 	freopen("357.in","r",stdin);
 	freopen("357.out","w",stdout);
//	puts("?");
	n=read();
	for(int i=1;i<n;++i){
		int u=read(),v=read(),w=read();
		link(u,v,w);
	}
	dfs(1,0,0);
//	cout<<dfn[7]<<" "<<siz[7]<<" "<<dfn[9]<<endl;
	m=read();
	for(int i=1;i<=m;++i)pos[i]=read();
	for(int i=1;i<=n;++i)if(siz[i]==1)Leaf.push_back(i);
//	for(auto v:Leaf)cout<<v<<endl;
	for(auto v:Leaf){
		int PP=v;
		for(int i=19;~i;--i)
			if(f[PP][i]&&f[f[PP][i]][0]>=1)
				PP=f[PP][i];
		anc[v]=PP;
	}
	int l=0,r=100000000000000ll;
	int ans=-1;
	while(l<=r){
		int mid=(l+r)>>1;
		if(check(mid))ans=mid,r=mid-1;
		else l=mid+1;
//		puts("");
	}
	cout<<ans<<endl;
	return 0;
}
// smaller