Submission #422644

#	Time	Username	Problem	Language	Result	Execution time	Memory
422644		milleniumEeee	Factories (JOI14_factories)	C++17	15 / 100	763 ms	143872 KiB

factories

#pragma GCC optimize("Ofast")
#include "factories.h"
#ifndef EVAL  
#include "grader.cpp"
#endif
 
	
#include <bits/stdc++.h>
#define fr first
#define sc second
#define pii pair<int, int>
#define pb push_back
#define szof(s) (int)s.size()
#define all(s) s.begin(), s.end()
#define ll long long
template<class T>void chmax(T &a,T b){if(a<b)a=b;}
template<class T>void chmin(T &a,T b){if(b<a)a=b;}
 
using namespace std;
 
const ll INF = 1e18;
const int MAXN = (int)5e5 + 5;
const int MAXQ = (int)1e5 + 5;
const int L = 19;
 
vector <pii> g[MAXN];
int n;
bool used[MAXN];
int sub[MAXN];
vector <int> G[MAXN];
int Gpar[MAXN];
ll opt[MAXN];
ll d[MAXN];
pii arr[MAXN];
int ind = 1;
pii bound[MAXN];

pii tb[MAXN * 2][L + 1];
int lg[MAXN * 2];
pii merge(pii a, pii b) {
	if (a.sc < b.sc) {
		return a;
	} else {
		return b;
	}
}
void build_table(int n) {
	lg[1] = 0;
	for (int i = 2; i <= n; i++) {
		lg[i] = lg[i >> 1] + 1;
	}
	for (int pw = 0; pw <= L; pw++) {
		for (int i = 1; i <= n; i++) {
			if (pw == 0) {
				tb[i][pw] = arr[i];
			}
			else if (i + (1 << pw) - 1 <= n) {
				tb[i][pw] = merge(tb[i][pw - 1], tb[i + (1 << (pw - 1))][pw - 1]);
			}
		}
	}
}
int get_lca(int a, int b) {
	int l = min(bound[a].fr, bound[b].fr);
	int r = max(bound[a].sc, bound[b].sc);
	int sz = lg[r - l + 1];
	pii lca = merge(tb[l][sz], tb[r - (1 << sz) + 1][sz]);
	return lca.fr;
}

void precalc(int v, int par, int dep = 0, ll len = 0) {
	arr[ind++] = {v, dep};
	d[v] = len;
	for (auto [to, dist] : g[v]) {
		if (to != par) {
			precalc(to, v, dep + 1, len + dist);
			arr[ind++] = {v, dep};
		}
	}
}

ll get_dist(int a, int b) {
	int lca = get_lca(a, b);
	return d[a] + d[b] - (d[lca] << 1);
}

 
void calc(int v, int par) {
	sub[v] = 1;
	for (auto [to, dist] : g[v]) {
		if (to != par && !used[to]) {
			calc(to, v);
			sub[v] += sub[to];
		}
	}
}
 
int find_centroid(int v, int par, int sz) {
	for (auto [to, dist] : g[v]) {
		if (to != par && sub[to] > (sz >> 1) && !used[to]) {
			return find_centroid(to, v, sz);
		}
	}
	return v;
}
 
void build(int v, int par) {
	calc(v, -1);
	int center = find_centroid(v, -1, sub[v]);
	used[center] = 1;
	if (par != -1) {
		G[center].pb(par);
		G[par].pb(center);
		Gpar[center] = par;
	}
	for (auto [to, dist] : g[center]) {
		if (!used[to]) {
			build(to, center);
		}
	}
}

void Init(int N, int A[], int B[], int D[]) {
	memset(Gpar, -1, sizeof(Gpar));
	fill(opt, opt + MAXN, INF);
	n = N;
	for (int i = 0; i < n - 1; i++) {
		int u = A[i];
		int v = B[i];
		int dist = D[i];
		g[u].pb({v, dist});
		g[v].pb({u, dist});
	}
	precalc(0, -1);
	for (int i = 0; i < n; i++) {
		bound[i] = {1e9, -1e9};
	}
	for (int i = 1; i < ind; i++) {
		int v = arr[i].fr;
		chmin(bound[v].fr, i);
		chmax(bound[v].sc, i);
	}
	build_table(ind - 1);
	build(0, -1);
}
void upd(int v, int type) {
	if (type == 1) {
		int cur = v;
		while (1) {
			if (cur == -1) {
				break;
			}
			opt[cur] = min(opt[cur], get_dist(cur, v));
			cur = Gpar[cur];
		}		
	}
	else {
		int cur = v;
		while (1) {
			if (cur == -1) {
				break;
			}
			opt[cur] = INF;
			cur = Gpar[cur];
		}
	}
}
 
ll get(int v) {
	ll ret = INF;
	int cur = v;
	while (1) {
		if (cur == -1) {
			break;
		}
		ret = min(ret, get_dist(v, cur) + opt[cur]);
		cur = Gpar[cur];
	}
	return ret;
}
 
ll Query(int S, int X[], int T, int Y[]) {
	ll ans = INF;
	for (int i = 0; i < S; i++) {
		upd(X[i], 1);
	}
	for (int i = 0; i < T; i++) {
		ans = min(ans, get(Y[i]));
	}
	for (int i = 0; i < S; i++) {
		upd(X[i], -1);
	}
	return ans;
}

• Subtask 1: 15 / 15
• Subtask 2: 0 / 18
• Subtask 3: 0 / 67