제출 #45324

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
45324		Noam527	Building Bridges (CEOI17_building)	C++11	0 / 100	125 ms	3880 KiB

building

#include <iostream>
#include <vector>
#include <algorithm>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
#include <string>
#include <time.h>
#include <stack>
#include <queue>
#include <random>
#include <fstream>
#define endl '\n'
#define flush fflush(stdout), cout.flush()
#define fast ios::sync_with_stdio(0), cin.tie(0), cout.tie(0)
#define debug cout << "ok" << endl
#define finish(x) return cout << x << endl, 0
typedef long long ll;
typedef long double ldb;
const int md = 1e9 + 7, inf = 1e9 + 7;
const ll hs = 199;
const ldb eps = 1e-9, pi = acos(-1);
using namespace std;

// maximum cht = type(1), minimum cht = type(-1)
struct cht {
	typedef long long ll;
	struct line {
		ll m, b, i, q;
		double nxt = 9e18;
		line(ll mm, ll bb, ll ii, ll qq = 0) : m(mm), b(bb), i(ii), q(qq) {};
		bool operator < (const line &x) const {
			if (!q && !x.q) return m < x.m;
			if (q) return m < x.nxt;
			return nxt < x.m;
		}
	};
	double cut(const line &x, const line &y) {
		return double(x.b - y.b) / (y.m - x.m);
	}
	int sign, nxtind = 0;
	cht(int type) {
		sign = type;
	}
	typedef set<line> s;
	s h;
	void upd(s::iterator &it) {
		if (next(it) != h.end()) {
			double n = cut(*it, *next(it));
			line l = *it;
			h.erase(it);
			l.nxt = n;
			it = h.insert(l).first;
		}
	}
	bool ok(s::iterator it) {
		if (it == h.begin() || next(it) == h.end() || cut(*prev(it), *it) < cut(*it, *next(it))) return true;
		return h.erase(it), false;
	}
	void insert(ll slope, ll constant) {
		line add(sign * slope, sign * constant, nxtind++);
		s::iterator it = h.insert(add).first;
		if (!ok(it)) return;
		while (it != h.begin() && !ok(prev(it)));
		while (next(it) != h.end() && !ok(next(it)));
		upd(it);
		if (it != h.begin()) upd(--it);
	}
	ll query(ll x) {
		line l = *h.lower_bound(line(x, 0, 0, 1));
		return sign * (x * l.m + l.b);
	}
	// returns the index of the best slope (indexed by the amount of lines tried to insert prior to it)
	ll iquery(ll x) {
		return h.lower_bound(line(x, 0, 0, 1))->i;
	}
};

int n;
vector<ll> h, w, sw, dp;
cht c(-1);

int main() {
	fast;
	cin >> n;
	h.resize(n);
	w.resize(n);
	sw.resize(n);
	dp.resize(n);
	for (auto &i : h) cin >> i;
	for (auto &i : w) cin >> i;
	sw[0] = w[0];
	for (int i = 1; i < n; i++) sw[i] = sw[i - 1] + w[i];
	
	dp[0] = 0;
//	cout << "for i " << 0 << " inserted " << dp[0] + h[0] * h[0] - sw[0] << " " << -2 * h[0] << endl;
	c.insert(-2 * h[0], dp[0] + h[0] * h[0] - sw[0]);
	for (int i = 1; i < n; i++) {
		dp[i] = c.query(h[i]) + sw[i - 1] + h[i] * h[i];
//		cout << "for i " << i << " inserted " << -2 * h[i] << " " << dp[i] + h[i] * h[i] - sw[i] << endl;
		c.insert(-2 * h[i], dp[i] + h[i] * h[i] - sw[i]);
	}
//	for (int i = 0; i < n; i++) cout << dp[i] << " "; cout << endl;
	cout << dp.back() << endl;
}

• Subtask 1: 0 / 30
• Subtask 2: 0 / 30
• Subtask 3: 0 / 40