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Time Traveller Imaxblue

Procesamos los portales y las consultas en orden inverso de tiempo. Mantenemos una cola de prioridad en cada vértice. Cada vez que vemos un portal, lo agregamos a cada uno de los portales a lo largo de su camino de centroides.

Complejidad temporal: O((N+Q)log⁡N+Mlog⁡2N)\mathcal{O}((N+Q)\log N+M\log^2N)

Complejidad espacial: O((N+M)log⁡N+Q)\mathcal{O}((N+M)\log N+Q)

#include <bits/stdc++.h>
using namespace std;
 
using ll = long long;
using ld = long double;
using db = double;
using str = string;  // yay python!
 
using pi = pair<int, int>;
using pl = pair<ll, ll>;
using pd = pair<db, db>;
 
using vi = vector<int>;
using vb = vector<bool>;
using vl = vector<ll>;
using vd = vector<db>;
using vs = vector<str>;
using vpi = vector<pi>;
using vpl = vector<pl>;
using vpd = vector<pd>;
 
#define tcT template <class T
#define tcTU tcT, class U
// ^ lol this makes everything look weird but I'll try it
tcT > using V = vector<T>;
tcT, size_t SZ > using AR = array<T, SZ>;
tcT > using PR = pair<T, T>;
 
// pairs
#define mp make_pair
#define f first
#define s second
 
// vectors
// oops size(x), rbegin(x), rend(x) need C++17
#define sz(x) int((x).size())
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define rall(x) x.rbegin(), x.rend()
#define sor(x) sort(all(x))
#define rsz resize
#define ins insert
#define ft front()
#define bk back()
#define pb push_back
#define eb emplace_back
#define pf push_front
 
#define lb lower_bound
#define ub upper_bound
tcT > int lwb(V<T> &a, const T &b) { return int(lb(all(a), b) - bg(a)); }
 
// loops
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define F0R(i, a) FOR(i, 0, a)
#define ROF(i, a, b) for (int i = (b) - 1; i >= (a); --i)
#define R0F(i, a) ROF(i, 0, a)
#define trav(a, x) for (auto &a : x)
 
const int MOD = 1e9 + 7;  // 998244353;
const int MX = 2e5 + 5;
const ll INF = 1e18;  // not too close to LLONG_MAX
const ld PI = acos((ld)-1);
const int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};  // for every grid problem!!
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count());
template <class T> using pqg = priority_queue<T, vector<T>, greater<T>>;
 
// bitwise ops
// also see https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html
constexpr int pct(int x) { return __builtin_popcount(x); }  // # of bits set
constexpr int bits(int x) {  // assert(x >= 0); // make C++11 compatible until
	                         // USACO updates ...
	return x == 0 ? 0 : 31 - __builtin_clz(x);
}  // floor(log2(x))
constexpr int p2(int x) { return 1 << x; }
constexpr int msk2(int x) { return p2(x) - 1; }
 
ll cdiv(ll a, ll b) {
	return a / b + ((a ^ b) > 0 && a % b);
}  // divide a by b rounded up
ll fdiv(ll a, ll b) {
	return a / b - ((a ^ b) < 0 && a % b);
}  // divide a by b rounded down
 
tcT > bool ckmin(T &a, const T &b) { return b < a ? a = b, 1 : 0; }  // set a = min(a,b)
tcT > bool ckmax(T &a, const T &b) { return a < b ? a = b, 1 : 0; }
 
tcTU > T fstTrue(T lo, T hi, U f) {
	hi++;
	assert(lo <= hi);  // assuming f is increasing
	while (lo < hi) {  // find first index such that f is true
		T mid = lo + (hi - lo) / 2;
		f(mid) ? hi = mid : lo = mid + 1;
	}
	return lo;
}
tcTU > T lstTrue(T lo, T hi, U f) {
	lo--;
	assert(lo <= hi);  // assuming f is decreasing
	while (lo < hi) {  // find first index such that f is true
		T mid = lo + (hi - lo + 1) / 2;
		f(mid) ? lo = mid : hi = mid - 1;
	}
	return lo;
}
tcT > void remDup(vector<T> &v) {  // sort and remove duplicates
	sort(all(v));
	v.erase(unique(all(v)), end(v));
}
tcTU > void erase(T &t, const U &u) {  // don't erase
	auto it = t.find(u);
	assert(it != end(t));
	t.erase(it);
}  // element that doesn't exist from (multi)set
 
// INPUT
#define tcTUU tcT, class... U
tcT > void re(complex<T> &c);
tcTU > void re(pair<T, U> &p);
tcT > void re(V<T> &v);
tcT, size_t SZ > void re(AR<T, SZ> &a);
 
tcT > void re(T &x) { cin >> x; }
void re(db &d) {
	str t;
	re(t);
	d = stod(t);
}
void re(ld &d) {
	str t;
	re(t);
	d = stold(t);
}
tcTUU > void re(T &t, U &...u) {
	re(t);
	re(u...);
}
 
tcT > void re(complex<T> &c) {
	T a, b;
	re(a, b);
	c = {a, b};
}
tcTU > void re(pair<T, U> &p) { re(p.f, p.s); }
tcT > void re(V<T> &x) { trav(a, x) re(a); }
tcT, size_t SZ > void re(AR<T, SZ> &x) { trav(a, x) re(a); }
tcT > void rv(int n, V<T> &x) {
	x.rsz(n);
	re(x);
}
 
// TO_STRING
#define ts to_string
str ts(char c) { return str(1, c); }
str ts(const char *s) { return (str)s; }
str ts(str s) { return s; }
str ts(bool b) {
#ifdef LOCAL
	return b ? "true" : "false";
#else
	return ts((int)b);
#endif
}
tcT > str ts(complex<T> c) {
	stringstream ss;
	ss << c;
	return ss.str();
}
str ts(V<bool> v) {
	str res = "{";
	F0R(i, sz(v)) res += char('0' + v[i]);
	res += "}";
	return res;
}
template <size_t SZ> str ts(bitset<SZ> b) {
	str res = "";
	F0R(i, SZ) res += char('0' + b[i]);
	return res;
}
tcTU > str ts(pair<T, U> p);
tcT > str ts(T v) {  // containers with begin(), end()
#ifdef LOCAL
	bool fst = 1;
	str res = "{";
	for (const auto &x : v) {
		if (!fst) res += ", ";
		fst = 0;
		res += ts(x);
	}
	res += "}";
	return res;
#else
	bool fst = 1;
	str res = "";
	for (const auto &x : v) {
		if (!fst) res += " ";
		fst = 0;
		res += ts(x);
	}
	return res;
 
#endif
}
tcTU > str ts(pair<T, U> p) {
#ifdef LOCAL
	return "(" + ts(p.f) + ", " + ts(p.s) + ")";
#else
	return ts(p.f) + " " + ts(p.s);
#endif
}
 
// OUTPUT
tcT > void pr(T x) { cout << ts(x); }
tcTUU > void pr(const T &t, const U &...u) {
	pr(t);
	pr(u...);
}
void ps() { pr("\n"); }  // print w/ spaces
tcTUU > void ps(const T &t, const U &...u) {
	pr(t);
	if (sizeof...(u)) pr(" ");
	ps(u...);
}
 
// DEBUG
void DBG() { cerr << "]" << endl; }
tcTUU > void DBG(const T &t, const U &...u) {
	cerr << ts(t);
	if (sizeof...(u)) cerr << ", ";
	DBG(u...);
}
#ifdef LOCAL  // compile with -DLOCAL, chk -> fake assert
#define dbg(...)                                                                       \
	cerr << "Line(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#define chk(...)                                                                       \
	if (!(__VA_ARGS__))                                                                \
		cerr << "Line(" << __LINE__ << ") -> function(" << __FUNCTION__                \
		     << ") -> CHK FAILED: (" << #__VA_ARGS__ << ")" << "\n",                   \
		    exit(0);
#else
#define dbg(...) 0
#define chk(...) 0
#endif
 
void setPrec() { cout << fixed << setprecision(15); }
void unsyncIO() { cin.tie(0)->sync_with_stdio(0); }
// FILE I/O
void setIn(str s) { freopen(s.c_str(), "r", stdin); }
void setOut(str s) { freopen(s.c_str(), "w", stdout); }
void setIO(str s = "") {
	unsyncIO();
	setPrec();
	// cin.exceptions(cin.failbit);
	// throws exception when do smth illegal
	// ex. try to read letter into int
	if (sz(s)) setIn(s + ".in"), setOut(s + ".out");  // for USACO
}
 
template <int SZ> struct CD {
	struct Edge {
		int a, b, w;
		int other(int x) { return a + b - x; }
	};
	vector<Edge> ed;
	vi adj[SZ];
 
	bool done[SZ];
	int sub[SZ], par[SZ];
	vl dist[SZ];
	pi cen[SZ];
 
	void addEdge(int a, int b, int w = 1) {
		adj[a].pb(sz(ed)), adj[b].pb(sz(ed));
		ed.pb({a, b, w});
	}
 
	void dfs(int x) {
		sub[x] = 1;
		trav(i, adj[x]) {
			int y = ed[i].other(x);
			if (!done[y] && y != par[x]) {
				par[y] = x;
				dfs(y);
				sub[x] += sub[y];
			}
		}
	}
 
	void genDist(int p, int x) {
		trav(i, adj[x]) {
			int y = ed[i].other(x);
			if (!done[y] && y != p) {
				cen[y] = cen[x];
				dist[y].pb(dist[x].back() + ed[i].w);
				genDist(x, y);
			}
		}
	}
 
	int centroid(int x) {
		par[x] = -1;
		dfs(x);
		for (int sz = sub[x];;) {
			pi mx = {0, 0};
			trav(i, adj[x]) {
				int y = ed[i].other(x);
				if (!done[y] && y != par[x]) ckmax(mx, {sub[y], y});
			}
			if (mx.f * 2 <= sz) return x;
			x = mx.s;
		}
	}
 
	void gen(int x, bool fst = 0) {  // call init(1) to start
		done[x = centroid(x)] = 1;
		dist[x].pb(0);  // exit(0);
		if (fst) cen[x].f = -1;
		int co = 0;
		trav(i, adj[x]) {
			int y = ed[i].other(x);
			if (!done[y]) {
				cen[y] = {x, co++};
				dist[y].pb(ed[i].w);
				genDist(x, y);
			}
		}
		trav(i, adj[x]) {
			int y = ed[i].other(x);
			if (!done[y]) gen(y);
		}
	}
 
	void init() { gen(0, 1); }
};
 
CD<MX> C;
int N, M, Q, T;
priority_queue<pair<ll, int>, vector<pair<ll, int>>, greater<pair<ll, int>>> pq[MX];
ll ans[MX];
 
void updEn(int ti, int x, ll cost) {
	pi cen = {x, -1};
	int ind = sz(C.dist[x]) - 1;
	for (; cen.f != -1; cen = C.cen[cen.f], ind--)
		pq[cen.f].push({cost + C.dist[x][ind], ti});
}
 
ll querySt(int ti, int x) {
	pi cen = {x, -1};
	int ind = sz(C.dist[x]) - 1;
	ll ans = INF;
	for (; cen.f != -1; cen = C.cen[cen.f], ind--) {
		while (sz(pq[cen.f]) && pq[cen.f].top().s > ti) pq[cen.f].pop();
		if (sz(pq[cen.f])) ckmin(ans, pq[cen.f].top().f + C.dist[x][ind]);
	}
	return ans;
}
 
int main() {
	setIO();
	re(N, M, Q, T);
	F0R(i, N - 1) {
		int X, Y, W;
		re(X, Y, W);
		C.addEdge(X, Y, W);
	}
	C.init();
	vector<array<int, 4>> mod;
	F0R(i, M) {
		int X, S, E, W;
		re(X, S, E, W);
		mod.pb({S, X, E, W});
	}
	F0R(i, Q) {
		int S, P;
		re(S, P);
		mod.pb({S, P, -1, i});
	}
	updEn(T, 0, 0);
	sort(mod.rbegin(), mod.rend());
	trav(t, mod) {
		ll z = querySt(t[0], t[1]);
		if (t[2] == -1) {
			ans[t[3]] = z;
		} else {
			if (z < INF) updEn(t[2], t[1], z + t[3]);
		}
	}
	F0R(i, Q) {
		if (ans[i] == INF) ps(-1);
		else ps(ans[i]);
	}
}
Fundamentos