Submission #985780

#	Time	Username	Problem	Language	Result	Execution time	Memory
985780		OAleksa	Harbingers (CEOI09_harbingers)	C++14	50 / 100	1084 ms	32852 KiB

harbingers

#include <bits/stdc++.h>
#define f first
#define s second
#define int long long
using namespace std;
const int N = 1e5 + 69;
struct line {
	int k, n;
	line(int _k, int _n) {
		k = _k;
		n = _n;
	}
	int val(int x) {
		return x * k + n;
	}
	double inter(line t) {
		return (double)(n - t.n) / (t.k - k);
	}
};
int n, s[N], w[N], dp[N], dep[N];
vector<pair<int, int>> g[N];
deque<pair<line, double>> dq;
void dfs(int v, int p) {
	int l = 0, r = dq.size() - 1, id = -1;
	while (l <= r) {
		int mid = (l + r) / 2;
		if ((double)w[v] >= dq[mid].s) {
			id = mid;
			l = mid + 1;
		}
		else
			r = mid - 1;
	}
	assert(id != -1);
	dp[v] = dq[id].f.val(w[v]) + s[v] + w[v] * dep[v];
	line ln = {-dep[v], dp[v]};
	vector<pair<line, int>> dead;
	while (dq.size() > 1 && ln.inter(dq.back().f) <= dq.back().s) {
		dead.push_back(dq.back());
		dq.pop_back();
	}
	double in = ln.inter(dq.back().f);
	dq.push_back({ln, in});
	for (auto u : g[v]) {
		if (u.f == p)
			continue;
		dep[u.f] = dep[v] + u.s;
		dfs(u.f, v);
	}
	if (dq.back().f.k == ln.k && dq.back().f.n == ln.n)
		dq.pop_back();
	while (!dead.empty()) {
		dq.push_back(dead.back());
		dead.pop_back();	
	}
}
signed main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int tt = 1;
  //cin >> tt;
  while (tt--) {
  	cin >> n;
  	for (int i = 1;i <= n - 1;i++) {
  		int a, b, c;
  		cin >> a >> b >> c;
  		g[a].push_back({b, c});
  		g[b].push_back({a, c});
  	}
  	for (int i = 2;i <= n;i++)
  		cin >> s[i] >> w[i];
  	dq.push_back({{0, 0}, 0});	
  	for (auto j : g[1]) {
  		dep[j.f] = j.s;
  		dfs(j.f, 1);
  	}
  	for (int i = 2;i <= n;i++)
  		cout << dp[i] << ' ';
  }
  return 0; 
}

• Subtask 1: 50 / 100