#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <chrono>
#define pb push_back
#define INF 0x3f3f3f3f
#define LINF 0x3f3f3f3f3f3f3f3f
#define endl '\n'
#define ll long long
#define f first
#define fin cin
#define fout cout
#define int long long
#define s second
#define FAST cin.tie(0), cout.tie(0), ios::sync_with_stdio(0)
#define debug(x) cout << "DEBUG " << x << endl
#define debug2(x, y) cout << "DEBUG " << x << " " << y << endl
#define debug3(x, y, z) cout << "DEBUG " << x << " " << y << " " << z<< endl
#define debug4(x, y, z, o) cout << "DEBUG " << x << " " << y << " " << z<< " " << o << endl
#define all(x) x.begin(), x.end()
#define left vadia
#define lb lower_bound
#define right puta
using namespace std;
using namespace __gnu_pbds;
void setIO(string s) {
ios_base::sync_with_stdio(0); cin.tie(0);
freopen((s+".in").c_str(),"r",stdin);
freopen((s+".out").c_str(),"w",stdout);
}
typedef pair<ll, ll> pii;
typedef vector<vector<char>> mat;
typedef pair<int, string> pis;
const ll mod = 998244353;
typedef vector<int> vi;
typedef pair<int, pair<int, int>> piii;
const int MAXN = 5e5+5;
int anc[MAXN][22], al[MAXN], h[MAXN], pai[MAXN], sz[MAXN], used[MAXN], best[MAXN];
vector<pii> g[MAXN];
int getsz(int u, int p) {
sz[u] = 1;
for(pii &i : g[u])
if(i.f != p && !used[i.f])
sz[u] += getsz(i.f, u);
return sz[u];
}
int findc(int u, int p, int n) {
for(pii &i : g[u])
if(i.f != p && !used[i.f] && sz[i.f] > n/2)
return findc(i.f, u, n);
return u;
}
void build(int u, int p) {
int c = findc(u, -1, getsz(u, -1));
used[c] = 1;
pai[c] = p;
for(pii &i : g[c])
if(!used[i.f])
build(i.f, c);
}
void dfs(int u) {
for(pii &i : g[u])
if(i.f != anc[u][0]) {
anc[i.f][0] = u;
al[i.f] = al[u] + 1;
h[i.f] = h[u] + i.s;
dfs(i.f);
}
}
int getlca(int a, int b) {
if(al[a] < al[b])
swap(a, b);
for(int i = 0; i <= 20; i++)
if( (1<<i) & (al[b] - al[a]) )
a = anc[a][i];
if(a == b)
return a;
for(int i = 20; i >= 0; i--)
if(anc[a][i] != anc[b][i])
a = anc[a][i], b = anc[b][i];
return anc[a][0];
}
int dist(int a, int b) {
return h[a] + h[b] - 2*h[getlca(a, b)];
}
void update(int u) {
int aux = u;
while(u != -1) {
best[u] = min(best[u], dist(aux, u));
//debug2(u, best[u]);
u = pai[u];
}
}
int query(int u) {
int aux = u, ans = LINF;
while(u != -1) {
ans = min(ans, best[u] + dist(aux, u));
u = pai[u];
}
return ans;
}
void reset(int u) {
int aux = u;
while(u != -1) {
best[u] = LINF;
u = pai[u];
}
}
int32_t main() {
int n, q;
cin >> n >> q;
for(int i = 0; i < n; i++)
best[i] = LINF;
for(int i = 1; i < n; i++) {
int a, b, c;
cin >> a >> b >> c;
g[a].pb({b, c});
g[b].pb({a, c});
}
dfs(0);
for(int j = 1; j < 22; j++)
for(int i = 1; i <= n; i++)
anc[i][j] = anc[anc[i][j-1]][j-1];
build(0, -1);
//debug(dist(2, 6));
while(q--) {
int s, t;
cin >> s >> t;
//debug("Mina san");
vector<int> v(s);
for(int i = 0; i < s; i++) {
int x;
cin >> x;
v[i] = x;
update(x);
}
int ans = LINF;
for(int i = 0; i < t; i++) {
int x;
cin >> x;
ans = min(ans, query(x));
}
cout << ans << endl;
for(int &i : v)
reset(i);
}
}
Compilation message
factories.cpp: In function 'void reset(long long int)':
factories.cpp:118:9: warning: unused variable 'aux' [-Wunused-variable]
118 | int aux = u;
| ^~~
factories.cpp: In function 'void setIO(std::string)':
factories.cpp:27:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
27 | freopen((s+".in").c_str(),"r",stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
factories.cpp:28:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
28 | freopen((s+".out").c_str(),"w",stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/bin/ld: /tmp/ccbxHYSx.o: in function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'; /tmp/ccBtGmkx.o:factories.cpp:(.text.startup+0x0): first defined here
/usr/bin/ld: /tmp/ccbxHYSx.o: in function `main':
grader.cpp:(.text.startup+0x37d): undefined reference to `Init(int, int*, int*, int*)'
/usr/bin/ld: grader.cpp:(.text.startup+0x412): undefined reference to `Query(int, int*, int, int*)'
collect2: error: ld returned 1 exit status
