Submission #883775

#	Time	Username	Problem	Language	Result	Execution time	Memory
883775		NK_	Two Currencies (JOI23_currencies)	C++17	100 / 100	2306 ms	39520 KiB

currencies

// Success consists of going from failure to failure without loss of enthusiasm
#include <bits/stdc++.h>

using namespace std;

#define nl '\n'
#define pb push_back
#define sz(x) int(x.size())

#define f first
#define s second
#define mp make_pair

using ll = long long;
template<class T> using V = vector<T>;
using pi = pair<int, int>;
using QRY = array<ll, 4>;
using vpi = V<pi>;
using vi = V<int>;
using vl = V<ll>;

const int LG = 18;

struct BIT {
	int N; vl A; void init(int n) { N = n; A = vl(N, 0); };
	void upd(int p, int x) { for(++p;p<=N;p+=p&-p) A[p-1] += x; }
	ll sum(int l, int r) { return sum(r + 1) - sum(l); }
	ll sum(int r) { ll s = 0; for(;r;r-=r&-r) s += A[r-1]; return s; }
};

int main() {
	cin.tie(0)->sync_with_stdio(0);
	
	int N, M, Q; cin >> N >> M >> Q;

	V<vpi> adj(N);
	for(int i = 0; i < N-1; i++) {
		int u, v; cin >> u >> v; --u, --v;
		adj[u].pb(mp(v, i));
		adj[v].pb(mp(u, i));
	}

	vpi C(M);
	for(auto& x : C) { cin >> x.s >> x.f; --x.s; }
	
	sort(begin(C), end(C));
	C.pb(mp(0, -1));

	V<QRY> qry(Q); 
	for(auto& x : qry) {
		cin >> x[0] >> x[1] >> x[2] >> x[3];
		--x[0], --x[1];
	}

	V<vi> up(N, vi(LG)); vi st(N), en(N), dep(N), EI(N-1); int t = 0;
	function<void(int, int)> gen = [&](int u, int p) {
		st[u] = t++;
		up[u][0] = p; for(int i = 1; i < LG; i++) up[u][i] = up[up[u][i-1]][i-1];

		for(auto& e : adj[u]) {
			auto [v, i] = e;
			if (v != p) {
				EI[i] = v; // v is the child of edge i
				dep[v] = dep[u] + 1;
				gen(v, u);
			}
		}

		en[u] = t - 1;
	};

	dep[0] = 0; gen(0, 0);

	assert(t == N);

	auto jmp = [&](int u, int d) {
		for(int i = 0; i < LG; i++) if ((d >> i) & 1) u = up[u][i];
		return u;
	};	

	auto lca = [&](int a, int b) {
		if (dep[a] < dep[b]) swap(a, b);
		a = jmp(a, dep[a] - dep[b]);

		if (a == b) return a;

		for(int i = LG - 1; i >= 0; --i) {
			if (up[a][i] != up[b][i]) {
				a = up[a][i], b = up[b][i];
			}
		}

		return up[a][0];
	};

	auto query = [&](BIT &T, int a, int b) {
		int l = lca(a, b);

		ll PA = T.sum(st[l], st[a]);
		ll PB = T.sum(st[l], st[b]);
		// cout << l << " " << a << " " << b << endl;

		return PA + PB - 2 * T.sum(st[l], st[l]);
	};

	BIT B; B.init(N + 1);
	for(int i = 0; i < M; i++) {
		auto [c, e] = C[i];
		int u = EI[e];
		B.upd(st[u], 1); B.upd(en[u] + 1, -1);
	}


	// Parallel Binsearch
	// Largest i value that is true (LST TRUE)
	vi lo(Q, -1), hi(Q, M); vpi ans(Q, mp(-1, -1));

	for(int r = 0; r < LG; r++) {
		vi mid(Q); for(int i = 0; i < Q; i++) {
			if (lo[i] >= hi[i]) mid[i] = -1;
			else mid[i] = (lo[i] + hi[i] + 1) / 2;
			// cout << i << " => " << mid[i] << endl;
		}

		vpi E; for(int i = 0; i < Q; i++) {
			if (mid[i] != -1) E.pb(mp(mid[i], i));
		}

		sort(begin(E), end(E));

		// cout << "E: "<< endl;
		// for(auto& x : E) cout << x.f << " " << x.s << endl;

		BIT S, P; S.init(N + 1), P.init(N + 1);
		for(int i = 0, cur = 0; i <= M; i++) {
			// cout << i << " => " << cur << endl;


			while(cur < sz(E) && E[cur].f == i) {
				// cout << E[cur].s << " " << i << endl;
				int idx = E[cur].s;

				ll s = query(S, qry[idx][0], qry[idx][1]); // silver on path
				ll p = query(P, qry[idx][0], qry[idx][1]); // checkpoints on path
				ll d = query(B, qry[idx][0], qry[idx][1]); // checkpoints on path (all checkpoints)
				ll g = d - p;

				// cout << idx << " -> " << qry[idx][0] << " " << qry[idx][1] << " " << qry[idx][2] << " " << qry[idx][3] << endl;
				// cout << s << " " << p << " " << d << " " << g << endl;
				// cout << idx << " ---> " << lo[idx] << " " << mid[idx] << " " << hi[idx] << endl;
				// cout << endl;

				if (s <= qry[idx][3]) {
					// cout << s << " <----> " << g << endl;
					lo[idx] = mid[idx];
					ans[idx] = mp(s, g);
					// cout << idx << " ---> " << lo[idx] << " " << hi[idx] << endl;
				} else hi[idx] = mid[idx] - 1;

				cur++;
			}

			if (i != M) {
				auto [c, e] = C[i];
				int u = EI[e];
				// cout << e << endl;
				// cout << u << " -> " << st[u] << endl;
				S.upd(st[u], c); S.upd(en[u] + 1, -c);
				P.upd(st[u], 1); P.upd(en[u] + 1, -1);
			}
		}
	}	
	// cout << endl << endl;

	for(int i = 0; i < Q; i++) {
		auto [a, b, g, s] = qry[i];
		auto [ns, ng] = ans[i];

		// cout << i << " ------> " << ns << " " << ng << endl;
		if (ns <= s && ng <= g) cout << g - ng << nl;
		else cout << -1 << nl;
	}

	exit(0-0);
}

• Subtask 1: 10 / 10
• Subtask 2: 28 / 28
• Subtask 3: 30 / 30
• Subtask 4: 32 / 32