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| #include <bits/stdc++.h> using namespace std; #pragma comment(linker, "/STACK:1024000000,1024000000") #define mem(a,b) memset((a),(b),sizeof(a)) #define MP make_pair #define pb push_back #define fi first #define se second #define sz(x) (int)x.size() #define all(x) x.begin(),x.end() using namespace __gnu_cxx; typedef long long ll; typedef unsigned long long ull; typedef pair<int,int> PII; typedef pair<ll,ll> PLL; typedef vector<int> VI; typedef vector<ll> VL; void go(); int main(){ #ifdef tokitsukaze freopen("TEST.txt","r",stdin); #endif go();return 0; } const int INF=0x3f3f3f3f; const ll LLINF=0x3f3f3f3f3f3f3f3f; const double PI=acos(-1.0); const double eps=1e-6; const int MAX=1e5+10; const ll mod=1e9+7;
struct node { int to; ll w; node(){} node(int _to,ll _w) :to(_to),w(_w){} }; ll dis[MAX],disred[MAX]; int path[2*MAX],deep[2*MAX],first[MAX],tot; int dp[2*MAX][20]; bool flag[MAX]; vector<node> mp[MAX]; void dfs(int x,int pre,int h) { int i; path[++tot]=x; first[x]=tot; deep[tot]=h; for(i=0;i<mp[x].size();i++) { int to=mp[x][i].to; if(to==pre) continue; disred[to]=min(disred[to],disred[x]+mp[x][i].w); dis[to]=dis[x]+mp[x][i].w; dfs(to,x,h+1); path[++tot]=x; deep[tot]=h; } } void ST(int n) { int i,j,x,y; for(i=1;i<=n;i++) { dp[i][0]=i; } for(j=1;(1<<j)<=n;j++) { for(i=1;i+(1<<j)-1<=n;i++) { x=dp[i][j-1]; y=dp[i+(1<<(j-1))][j-1]; dp[i][j]=deep[x]<deep[y]?x:y; } } } int query(int l,int r) { int len,x,y; len=(int)log2(r-l+1); x=dp[l][len]; y=dp[r-(1<<len)+1][len]; return deep[x]<deep[y]?x:y; } int LCA(int x,int y) { int l,r,pos; l=first[x]; r=first[y]; if(l>r) swap(l,r); pos=query(l,r); return path[pos]; } int getdist(int a,int b) { return dis[a]+dis[b]-2*dis[LCA(a,b)]; } void work(int n) { int i; for(i=1;i<=n;i++) dis[i]=0; tot=0; dfs(1,0,0); ST(2*n-1); } int tmp[MAX]; void go() { int t,n,m,q,i,a,b,w,k; ll l,r,mid; read(t); while(t--) { read(n,m,q); for(i=1;i<=n;i++) { mp[i].clear(); disred[i]=LLINF; } while(m--) { read(a); disred[a]=0; } for(i=1;i<n;i++) { read(a,b,w); mp[a].pb(node(b,w)); mp[b].pb(node(a,w)); } work(n); while(q--) { read(k); l=r=0; for(i=1;i<=k;i++) { read(tmp[i]); r=max(r,dis[tmp[i]]); } VI res; auto check=[&](ll x)->int { res.clear(); for(i=1;i<=k;i++) { if(disred[tmp[i]]>x) res.pb(tmp[i]); } if(sz(res)<=1) return 1; int lca=res[0]; for(i=1;i<sz(res);i++) lca=LCA(lca,res[i]); for(i=0;i<sz(res);i++) { if(dis[res[i]]-dis[lca]>x) return 0; } return 1; }; while(l<r) { mid=(l+r)>>1; if(check(mid)) r=mid; else l=mid+1; } printf("%lld\n",l); } } }
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