Submission #542245

#	Time	Username	Problem	Language	Result	Execution time	Memory
542245		fcw	Harbingers (CEOI09_harbingers)	C++17	90 / 100	1063 ms	27356 KiB

harbingers

#include <bits/stdc++.h>
#define st first
#define nd second
using lint = int64_t;
constexpr int mod = int(1e9) + 7;
constexpr int inf = 0x3f3f3f3f;
constexpr int ninf = 0xcfcfcfcf;
constexpr lint linf = 0x3f3f3f3f3f3f3f3f;
const long double pi = acosl(-1.0);
// Returns -1 if a < b, 0 if a = b and 1 if a > b.
int cmp_double(double a, double b = 0, double eps = 1e-9) {
	return a + eps > b ? b + eps > a ? 0 : 1 : -1;
}
using namespace std;

struct Line{
	mutable lint k, m, p;
	bool operator<(const Line& o) const { return k < o.k; }
	bool operator<(lint x) const {return p < x; }
};
struct LineContainer : multiset<Line, less<>>{
	static const lint inf = LLONG_MAX;
	lint div(lint a, lint b){
		return a / b - ((a ^ b) < 0 && a % b);
	}
	bool isect(iterator x, iterator y){
		if(y == end()){ x->p = inf; return false; }
		if(x->k == y->k) x->p = x->m > y->m ? inf : -inf;
		else x->p = div(y->m - x->m, x->k - y->k);
		return x->p >= y->p;
	}
	void add(lint k, lint m){
		auto z = insert({k, m, 0}), y = z++, x = y;
		while(isect(y, z)) z = erase(z);
		if(x != begin() && isect(--x, y)) isect(x, y = erase(y));
		while((y = x) != begin() && (--x)->p >= y->p)
			isect(x, erase(y));
	}
	lint query(lint x){
		assert(!empty());
		auto l = *lower_bound(x);
		return l.k * x + l.m;
	}
};


int main() {
	cin.tie(nullptr)->sync_with_stdio(false);
	int n;
	cin>>n;
	vector<vector<pair<int, int>>>g(n);
	for(int i=1;i<n;i++){
		int a, b, c;
		cin>>a>>b>>c;
		a--, b--;
		g[a].push_back({b, c});
		g[b].push_back({a, c});
	}
	vector<lint>s(n), v(n);
	for(int i=1;i<n;i++) cin>>s[i]>>v[i];
	int sz = sqrt(n * log(n));
	vector<lint>dist(n), dp(n, linf);
	dp[0] = 0;
	vector<int>par(n);
	vector<LineContainer>st;
	auto dfs = [&](auto& self, int u, int p, int d)->void{
		par[u] = p;
		if(d && d % sz == 0){
			st.push_back(LineContainer());
			LineContainer& cht = st.back();
			for(int i=0,x=par[u];i<sz;i++,x=par[x]){
				cht.add(dist[x], -dp[x]);
			}
		}
		{
			// calculate ans
			lint cnt = dist[u] * v[u] + s[u];
			dp[u] = cnt;
			for(int i=0,x=par[u];i<d%sz;i++,x=par[x]){
				dp[u] = min(dp[u], cnt - dist[x] * v[u] + dp[x]);
			}
			for(auto& cht : st){
				dp[u] = min(dp[u], cnt - cht.query(v[u]));
			}
		}
		for(auto [nxt, c] : g[u]){
			if(nxt == p) continue;
			dist[nxt] = dist[u] + c;
			self(self, nxt, u, d+1);
		}
		if(d && d % sz == 0) st.pop_back();
	};
	dfs(dfs, 0, 0, 0);
	for(int i=1;i<n;i++) cout<<dp[i]<<" ";
	cout<<"\n";

	return 0;
}
/*
[  ]Leu o problema certo???
[  ]Ver se precisa de long long
[  ]Viu o limite dos fors (é n? é m?)
[  ]Tamanho do vetor, será que é 2e5 em vez de 1e5??
[  ]Testar sample
[  ]Testar casos de  borda
[  ]1LL no 1LL << i
[  ]Testar mod (é 1e9+7, mesmo?, será que o mod não ficou negativo?)
*/

• Subtask 1: 90 / 100