Submission #716978

#	Time	Username	Problem	Language	Result	Execution time	Memory
716978		thiago_bastos	Harbingers (CEOI09_harbingers)	C++17	20 / 100	170 ms	44024 KiB

harbingers

#include "bits/stdc++.h"

using namespace std;
 
#define INF   1000000000
#define INFLL 1000000000000000000ll
#define EPS 1e-9
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define pb push_back
#define fi first
#define sc second
 
using i64 = long long;
using u64 = unsigned long long;
using ld = long double;
using ii = pair<int, int>;
using i128 = __int128;

const int N = 1e5 + 10;

vector<ii> adj[N];
int n, dist[N], s[N], vel[N], coords[N];
i64 dp[N];

using T = pair<int, i64>;
T st[4 * N];
vector<pair<int,T>> changes;
int cnt_changes;

void initialize() {
	fill(st, st + 4 * n, make_pair(0ll, INFLL));
}

void insert(int a, i64 b, int l, int r, int p = 1) {
	int m = (l + r) / 2;
	bool v1 = (i64)a * coords[l] + b < (i64)st[p].fi * coords[l] + st[p].sc;
	bool v2 = (i64)a * coords[m] + b < (i64)st[p].fi * coords[m] + st[p].sc;
	if(v2) {
		changes.pb({p, st[p]});
		swap(st[p].fi, a);
		swap(st[p].sc, b);
		++cnt_changes;
	}
	if(l == r) return;
	else if(v1 != v2) insert(a, b, l, m, 2 * p);
	else insert(a, b, m + 1, r, 2 * p + 1);
}

int insert(int a, i64 b) {
	cnt_changes = 0;
	insert(a, b, 0, n - 1);
	return cnt_changes;
}

i64 get(int x, int l, int r, int p = 1) {
	i64 y = st[p].fi * x + st[p].sc;
	if(l == r) return y;
	int m = (l + r) / 2;
	i64 z = x <= coords[m] ? get(x, l, m, 2 * p) : get(x, m + 1, r, 2 * p + 1);
	return min(y, z);
}

void undo() {
	auto [p, f] = changes.back();
	st[p] = f;
	changes.pop_back();
}

void dfs(int u, int p) {
	if(u != p) dp[u] = get(vel[u], 0, n - 1) + s[u] + (i64)dist[u] * vel[u];
	else dp[u] = 0;
	int cnt = insert(-dist[u], dp[u]);
	for(auto [v, l] : adj[u]) {
		if(v == p) continue;
		dist[v] = dist[u] + l;
		dfs(v, u);
	}
	while(cnt--) undo();
}

void solve() {
	cin >> n;
	for(int i = 1; i < n; ++i) {
		int a, b, c;
		cin >> a >> b >> c;
		--a, --b;
		adj[a].pb({b, c});
		adj[b].pb({a, c});
	}
	for(int i = 1; i < n; ++i) {
		cin >> s[i] >> vel[i];
		coords[i] = vel[i];
	}
	sort(coords, coords + n);
	initialize();
	dfs(0, 0);
	for(int i = 1; i < n; ++i) cout << dp[i] << ' ';
	cout << '\n';
}

int main() {
	ios_base :: sync_with_stdio(false);
	cin.tie(0);
	int t = 1;
  	//cin >> t;
	while(t--) solve();
	return 0;
}

• Subtask 1: 20 / 100