Red Black Tree ZOJ - 4048

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LCA+二分

#include <bits/stdc++.h>
#define mem(ar,num) memset(ar,num,sizeof(ar))
#define me(ar) memset(ar,0,sizeof(ar))
#define lowbit(x) (x&(-x))
#define Pb push_back
#define  FI first
#define  SE second
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define IOS ios::sync_with_stdio(false)
#define DEBUG cout<<endl<<"DEBUG"<<endl; 
using namespace std;
typedef long long LL;
typedef unsigned long long ULL;
const int    prime = 999983;
const int    INF = 0x7FFFFFFF;
const LL     INFF =0x7FFFFFFFFFFFFFFF;
const double pi = acos(-1.0);
const double inf = 1e18;
const double eps = 1e-6;
const LL     mod = 1e9 + 7;
LL qpow(LL a,LL b){LL s=1;while(b>0){if(b&1)s=s*a%mod;a=a*a%mod;b>>=1;}return s;}
LL gcd(LL a,LL b) {return b?gcd(b,a%b):a;}
int dr[2][4] = {1,-1,0,0,0,0,-1,1};
typedef pair<int,int> P;
const int maxn = 2e5+100;
const int maxlogv = 19;
bool red[maxn];
struct Edge{
	int to,weight;
	Edge(int t,int w):to(t),weight(w){};
};
vector<Edge> G[maxn];
int id[maxn];
LL dis[maxn];
LL dist[maxn];
int vs[maxn*2],depth[maxn*2];
int dp[maxn*2][maxlogv];
void dfs(int node,int fa,int d,int &k){
   	id[node] = k;
   	vs[k] = node;
 	depth[k++] = d;
 	// dis[node] = distance;
 	for(int i = 0;i < G[node].size(); ++i){
 		Edge &t = G[node][i];
 		if(t.to == fa) continue;
 		if(!red[t.to])
 		   dis[t.to] = dis[node]+t.weight;
 		else
 		   dis[t.to] = 0;
 		dist[t.to] = dist[node] + t.weight;
 		// cout<<dis[t.to]<<endl;
 		// cout<<t.weight<<endl;
 		dfs(t.to,node,d+1,k);
        vs[k] = node;
        depth[k++] = d;
 	}
}

void init_rmq(int n){
	
	for(int i = 0;i < n ; ++i) dp[i][0] = i;
    for(int j = 1;(1<<j) <= n; ++j){
    	for(int i = 0;i + (1<<j)-1 < n; ++i){
    		if(depth[dp[i][j-1]]< depth[dp[i+(1<<(j-1))][j-1]])
    			dp[i][j] = dp[i][j-1];
    		else
    			dp[i][j] = dp[i+(1<<(j-1))][j-1];

    	}
    }
}
int query(int l,int r){
	int k = 0;
	while((1<<(k+1)) <= r-l+1) k++;
 	if(depth[dp[l][k]] < depth[dp[r-(1<<k)+1][k]])
 		return dp[l][k];
 	else 
 		return dp[r-(1<<k)+1][k];
}
int lca(int u,int v){
	return vs[query(min(id[u],id[v]),max(id[u],id[v]))];
}

// const int maxn = 1e5+1000;
// 
int b[maxn];
bool check(int kk,LL mid){
  bool yes = true;
  int fa;
  for(int i = 1;i <= kk; ++i){
  	  if(dis[b[i]] > mid){
  	  	if(yes){
  	  			yes = false;
  	  			fa = b[i];
  	  	}
  	  	else
  	  		fa = lca(fa,b[i]);
  	  }
  }
  if(yes) return true;
  for(int  i = 1;i <= kk; ++i){
  		if(dis[b[i]] > mid){
  			if(dist[b[i]] - dist[fa]  > mid)
  				return false;
  		}
  }
  return true;
}
// #define Debug
int main(void)
{
	#ifdef Debug
	freopen("input.txt","r",stdin);
	freopen("output.txt","w+",stdout);
	#endif
	int T;
	int n,m,q;
	cin>>T;
	while(T--){
		me(red);
		scanf("%d%d%d",&n,&m,&q);
		for(int i = 0;i < n; ++i) G[i].clear();
		for(int i = 0;i < m; ++i) {
			int a;
			scanf("%d",&a);
			a--;
			red[a] = true;
		}
		for(int i = 1;i < n; ++i){
			int u,v,w;
			scanf("%d%d%d",&u,&v,&w);
			u--,v--;
			G[u].Pb(Edge(v,w));
			// cout<<w<<endl;
			G[v].Pb(Edge(u,w));
		}
		int k = 0;
	 	dfs(0,-1,0,k);
		init_rmq(2*n-1);
		// /*for(int i = 0;i < n; ++i )cout<<dis[i]<<" ";
		while(q--){
			int kk;
			scanf("%d",&kk);
			for(int i = 1;i <= kk;++i) scanf("%d",&b[i]),b[i]--;

			LL l = 0,r = 1e14;

			while(r >= l){
				LL mid = (r+l)>>1;
				if(check(kk,mid)){
					r = mid-1;
				}  
				else
					l = mid+1;
			}
			printf("%lld\n",l);
			
		}
	}
    return 0;
}