Submission #305619

#	Time	Username	Problem	Language	Result	Execution time	Memory
305619		youngyojun	Construction of Highway (JOI18_construction)	C++17	100 / 100	696 ms	26616 KiB

construction

#include <bits/stdc++.h>
#define pb push_back
#define eb emplace_back
#define sz(V) ((int)(V).size())
#define allv(V) ((V).begin()),((V).end())
#define befv(V) ((V)[(sz(V)-2)])
#define sorv(V) sort(allv(V))
#define revv(V) reverse(allv(V))
#define univ(V) (V).erase(unique(allv(V)),(V).end())
#define clv(V) (V).clear()
#define upmin(a,b) (a)=min((a),(b))
#define upmax(a,b) (a)=max((a),(b))
#define rb(x) ((x)&(-(x)))
#define INF (0x3f3f3f3f)
#define INFLL (0x3f3f3f3f3f3f3f3fll)
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
 
const int MAXN = 100055;
 
struct BIT {
	int d[MAXN];
	void upd(int x, int r) {
		for(x += 2; x < MAXN; x += rb(x))
			d[x] += r;
	}
	int get(int x) {
		int r = 0; for(x += 2; x; x -= rb(x))
			r += d[x];
		return r;
	}
} bit;
 
struct HLD {
	set<pii> V;
	int rprt, n;
 
	void init(int _n) {
		n = _n;
	}
 
	void get(vector<pii> &PQ, int i) {
		vector<pii> T;
 
		for(auto it = V.lower_bound(pii(i, -INF));; it--) {
			T.eb(min(i, it -> first), it -> second);
			if(V.begin() == it) break;
		}
		T.eb(-1, -1);
 
		for(int i = 1, n = sz(T), l, x; i < n; i++) {
			l = T[i-1].first - T[i].first;
			x = T[i-1].second;
			if(!l) continue;
 
			if(PQ.empty() || PQ.back().first != x) PQ.eb(x, l);
			else PQ.back().second += l;
		}
	}
	void upd(int i, int c) {
		for(; !V.empty();) {
			auto it = V.begin();
			if(i < it -> first) break;
			V.erase(it);
		}
		V.insert(pii(i, c));
	}
} hld[MAXN];
 
vector<int> G[MAXN];
 
int HI[MAXN], HJ[MAXN], HSZ[MAXN], Hn;
 
int prt[MAXN], dep[MAXN], cnt[MAXN], depo[MAXN];
 
int A[MAXN], B[MAXN], C[MAXN];
 
int N;
 
void f(vector<pii> &V, int i) {
	for(; i; i = hld[HI[i]].rprt)
		hld[HI[i]].get(V, HJ[i]);
}
void g(int i, int c) {
	for(; i; i = hld[HI[i]].rprt)
		hld[HI[i]].upd(HJ[i], c);
}
 
ll getRev(vector<pii> &V) {
	{
		vector<int> VX;
		for(auto &v : V) VX.pb(v.first);
		sorv(VX); univ(VX);
		for(auto &v : V)
			v.first = (int)(lower_bound(allv(VX), v.first) - VX.begin()) + 1;
	}
 
	ll ret = 0;
	for(auto &v : V) {
		ret += ll(bit.get(v.first-1)) * v.second;
		bit.upd(v.first, v.second);
	}
	for(auto &v : V) bit.upd(v.first, -v.second);
	return ret;
}
 
void dfs1(int i) {
	cnt[i] = 1;
	for(int v : G[i]) {
		dep[v] = dep[i] + 1;
		prt[v] = i;
		dfs1(v);
		cnt[i] += cnt[v];
	}
}
void dfs2(int i) {
	HJ[i] = HSZ[HI[i]]++;
	int hi = -1, hc = -1;
	for(int v : G[i]) {
		if(cnt[v] <= hc) continue;
		hi = v; hc = cnt[v];
	}
	if(hi < 0) return;
	HI[hi] = HI[i];
	dfs2(hi);
}
 
int main() {
	ios::sync_with_stdio(false);
 
	cin >> N;
	for(int i = 1; i <= N; i++) cin >> C[i];
	for(int i = 1; i < N; i++) cin >> A[i] >> B[i];
 
	for(int i = 1; i < N; i++) G[A[i]].pb(B[i]);
	dep[1] = 1; dfs1(1);
 
	iota(depo, depo+N+1, 0);
	sort(depo+1, depo+N+1, [&](int a, int b) { return dep[a] < dep[b]; });
	for(int oi = 1, i; oi <= N; oi++) {
		i = depo[oi];
		if(HI[i]) continue;
		Hn++; HI[i] = Hn;
		dfs2(i);
	}
 
	for(int i = 1; i <= Hn; i++) hld[i].init(HSZ[i]);
	for(int i = 1; i <= N; i++) {
		hld[HI[i]].V.insert(pii(HJ[i], C[i]));
		if(!HJ[i]) hld[HI[i]].rprt = prt[i];
	}
 
	for(int qi = 1, a, b; qi < N; qi++) {
		a = A[qi]; b = B[qi];
 
		vector<pii> V; f(V, a);
		printf("%lld\n", getRev(V));
		g(b, C[b]);
	}
	return 0;
}

• Subtask 1: 7 / 7
• Subtask 2: 9 / 9
• Subtask 3: 84 / 84