This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define fr first
#define sc second
#define clr(a, x) memset(a, x, sizeof(a))
#define dbg(x) cout<<"("<<#x<<"): "<<x<<endl;
#define printvector(arr) for (auto it = arr.begin(); it != arr.end(); ++it) cout<<*it<<" "; cout<<endl;
#define all(v) v.begin(), v.end()
#define lcm(a, b) (a * b)/__gcd(a, b)
#define int long long int
#define printvecpairs(vec) for(auto it: vec) cout<<it.fr<<' '<<it.sc<<endl;
#define endl '\n'
#define pii pair<int, int>
#define float long double
const int MOD = 1e9 + 7;
const int INF = 2e15;
const int MAXN = 1e5 + 5;
int n, m, k, l;
vector<pii> adj[MAXN];
vector<int> mst[MAXN];
int dist[MAXN], b[MAXN], up[MAXN][100], tout[MAXN], tin[MAXN], upmn[MAXN][100], depth[MAXN];
int timer = 0;
void dfs(int v, int p, int d = 0){
timer++;
tin[v] = timer;
up[v][0] = p;
upmn[v][0] = min(dist[v], dist[p]);
for(int i=1;i<=l;i++){
up[v][i] = up[up[v][i-1]][i-1];
upmn[v][i] = min(upmn[up[v][i-1]][i-1], upmn[v][i-1]);
}
depth[v] = d;
for(int u: mst[v]){
if(u != p){
dfs(u, v, d+1);
}
}
timer++;
tout[v] = timer;
}
bool isanc(int a, int b){
return tin[a] <= tin[b] && tout[a] >= tout[b];
}
int lca(int u, int v){
if(isanc(u, v)) return u;
if(isanc(v, u)) return v;
for(int i = l;i >= 0;i--){
if(!isanc(up[u][i], v)){
u = up[u][i];
}
}
return up[u][0];
}
int getmn(int u, int kx){
int ans = dist[u];
for(int i= 0;i<=l;i++){
if(kx & (1<<i)){
ans = min(ans, upmn[u][i]);
u = up[u][i];
}
}
return ans;
}
void dstra(){
for(int i=1;i<=n;i++){
dist[i] = INF;
}
priority_queue<pii> pq;
for(int j= 1;j<=k;j++){
dist[b[j]] = 0;
pq.push({0, b[j]});
}
while(!pq.empty()){
int u = pq.top().sc;
pq.pop();
for(auto e: adj[u]){
int w = e.sc, v = e.fr;
if(dist[u]+w < dist[v]){
dist[v] = dist[u] + w;
pq.push({-dist[v], v});
}
}
}
}
int parent[MAXN] = {-1};
void init(){
for(int i= 1;i<=n;i++) parent[i] = i;
timer = 0;
clr(tout, 0);
clr(tin, 0);
l = ceil(log2(n));
clr(up, 0);
}
int find_set(int s){
if(s == parent[s]){
return s;
}
return parent[s] = find_set(parent[s]);
}
bool union_sets(int a, int b){
a = find_set(a);
b = find_set(b);
if(a != b){
parent[b] = a;
return true;
} else {
return false;
}
}
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
#ifdef LOCAL
freopen("input.txt", "r", stdin);
#endif
cin>>n>>m;
vector<pii> edges;
for(int i=0;i<m;i++){
int u, v, w;
cin>>u>>v>>w;
adj[u].pb({v, w});
adj[v].pb({u, w});
edges.pb({u, v});
}
cin>>k;
for(int i= 1;i<=k;i++){
cin>>b[i];
}
dstra();
init();
vector<pair<int, pii>> wedges;
for(auto edge: edges){
wedges.pb({min(dist[edge.fr], dist[edge.sc]), {edge}});
}
sort(all(wedges));
reverse(all(wedges));
for(auto edge: wedges){
int u = edge.sc.fr, v = edge.sc.sc;
if(union_sets(u, v)){
mst[v].pb(u);
mst[u].pb(v);
}
}
dfs(1, 1);
int q;
cin>>q;
while(q--){
int u, v;
cin>>u>>v;
int lc = lca(u, v);
int du = depth[u]-depth[lc];
int dv = depth[v]-depth[lc];
cout<<min(getmn(u, du), getmn(v, dv))<<endl;
}
return 0;
}
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