Submission #716970

#	Time	Username	Problem	Language	Result	Execution time	Memory
716970		thiago_bastos	Harbingers (CEOI09_harbingers)	C++17	30 / 100	187 ms	50448 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, X = 1e4 + 10;

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

pair<i64, i64> st[4 * X];
vector<tuple<int,pair<i64,i64>,int>> changes;
int curChange;

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

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

void insert(i64 a, i64 b) {
	insert(a, b, 0, X - 1);
	++curChange;
}

i64 get(int x, int l = 0, int r = X - 1, 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 <= 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]) + s[u] + (i64)dist[u] * vel[u];
	else dp[u] = 0;
	int cur = curChange;
	insert(-dist[u], dp[u]);
	for(auto [v, l] : adj[u]) {
		if(v == p) continue;
		dist[v] = dist[u] + l;
		dfs(v, u);
	}
	while(!changes.empty() && get<2>(changes.back()) == cur) 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];
	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: 30 / 100