Submission #102664

#	Time	Username	Problem	Language	Result	Execution time	Memory
102664		Minnakhmetov	Bulldozer (JOI17_bulldozer)	C++14	5 / 100	12 ms	1612 KiB

bulldozer

#include <algorithm>
#include <bitset>
#include <complex>
#include <deque>
#include <exception>
#include <fstream>
#include <functional>
#include <iomanip>
#include <ios>
#include <iosfwd>
#include <iostream>
#include <istream>
#include <iterator>
#include <limits>
#include <list>
#include <locale>
#include <map>
#include <memory>
#include <new>
#include <numeric>
#include <ostream>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <stdexcept>
#include <streambuf>
#include <string>
#include <typeinfo>
#include <utility>
#include <valarray>
#include <vector>
#include <cstring>
#include <unordered_map>
#include <unordered_set>

using namespace std;

#define ll long long
#define all(aaa) aaa.begin(), aaa.end()
#pragma warning(disable : 4996)

ll gcd(ll a, ll b) {
	return a ? gcd(b % a, a) : b;
}

struct P {
	int x, y, w;
	void normalize() {
		int g = gcd(x, y);
		x /= g;
		y /= g;
		if (y < 0 || y == 0 && x < 0) {
			x = -x;
			y = -y;
		}
	}
	bool operator < (const P &oth) const {
		int q1 = x <= 0,
			q2 = oth.x <= 0;
		return q1 == q2 ? (x * oth.y - y * oth.x > 0) : q1 < q2;
	}
};

struct Line {
	ll a, b, c;
	P orth_vec;
	Line(P &p, P &q) {
		a = p.y - q.y;
		b = q.x - p.x;
		c = -p.y * (ll)(q.x - p.x) + (q.y - p.y) * (ll)p.x;

		ll g = gcd(gcd(a, b), c);

		a /= g;
		b /= g;
		c /= g;

		if (a < 0 || a == 0 && b < 0) {
			a = -a;
			b = -b;
			c = -c;
		}

		orth_vec = { q.y - p.y, p.x - q.x };
		orth_vec.normalize();
	}
	bool operator < (const Line &oth) const {
		if (a == oth.a)
			return b == oth.b ? c < oth.c : b < oth.b;
		return a < oth.a;
	}
};

const ll INF = 1e18;
const int N = 2005;
P a[N];
ll t[N * 4], mnp[N * 4], mxp[N * 4], pref[N], up[N * 4];
int pos[N];
int n;

map<P, map<Line, vector<int>>> mp;

void mrg(int v) {
	t[v] = max(t[v * 2], t[v * 2 + 1]);
	t[v] = max(t[v], mxp[v * 2 + 1] - mnp[v * 2]);
	mxp[v] = max(mxp[v * 2], mxp[v * 2 + 1]);
	mnp[v] = min(mnp[v * 2], mnp[v * 2 + 1]);
}

void build(int v = 1, int L = 0, int R = n) {
	if (L == R) {
		t[v] = 0;
		mxp[v] = mnp[v] = pref[L];
	}
	else {
		int m = (L + R) >> 1;
		build(v * 2, L, m);
		build(v * 2 + 1, m + 1, R);
		mrg(v);
	}
}

void push(int v, int L, int R) {
	if (up[v]) {
		if (L != R) {
			up[v * 2] += up[v];
			up[v * 2 + 1] += up[v];
		}
		mnp[v] += up[v];
		mxp[v] += up[v];
		up[v] = 0;
	}
}

void upd(int l, int r, int x, int v = 1, int L = 0, int R = n) {
	push(v, L, R);
	if (l > r)
		return;
	if (l == L && r == R) {
		up[v] += x;
		push(v, L, R);
	}
	else {
		int m = (L + R) >> 1;
		upd(l, min(m, r), x, v * 2, L, m);
		upd(max(m + 1, l), r, x, v * 2 + 1, m + 1, R);
		mrg(v);
	}
}


P tmp[N];

void print() {

	for (int i = 1; i <= n; i++) {
		tmp[pos[i]] = a[i];
	}
	for (int i = 1; i <= n; i++)
		cout << tmp[i].w << " ";
	cout << "\n";
	for (int i = 1; i <= n; i++)
		cout << tmp[i].x << " " << tmp[i].y << "\n";
	cout << "\n";
}

signed main() {
#ifdef HOME
	freopen("input.txt", "r", stdin);
	freopen("output.txt", "w", stdout);
#endif
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	cin >> n;

	for (int i = 1; i <= n; i++) {
		int x, y, w;
		cin >> x >> y >> w;
		a[i] = { x, y, w };
	}

	sort(a + 1, a + n + 1, [](P &a, P &b) {
		return a.x == b.x ? a.y > b.y : a.x < b.x;
	});

	for (int i = 1; i <= n; i++) {
		pos[i] = i;
		pref[i] = pref[i - 1] + a[i].w;
		for (int j = i + 1; j <= n; j++) {
			Line l(a[i], a[j]);
			mp[l.orth_vec][l].push_back(i);
			mp[l.orth_vec][l].push_back(j);
		}
	}

	build();

	for (auto &i : mp) {
		for (auto &j : i.second) {
			sort(all(j.second));
			j.second.erase(unique(all(j.second)), j.second.end());
		}
	}

	ll ans = t[1];

	//print();

	for (auto &ev : mp) {
		for (auto &l : ev.second) {
			int lb = N, rb = -1;
			for (int x : l.second) {
				lb = min(lb, pos[x]);
				rb = max(rb, pos[x]);
				upd(pos[x], n, -a[x].w);
			}
			for (int x : l.second) {
				pos[x] = rb - pos[x] + lb;
				upd(pos[x], n, a[x].w);
			}
		}

		///*if (t[1] == 17) {
		//	cout << "-> " << ev.first.x << " " << ev.first.y << "\n";
		//	print();
		//}*/


		//cout << "-> " << ev.first.x << " " << ev.first.y << "\n";
		//cout << "ans : " << t[1] << "\n";
		//print();


		ans = max(ans, t[1]);
	}

	cout << ans;

	return 0;
}

Compilation message (stderr)

bulldozer.cpp:41:0: warning: ignoring #pragma warning  [-Wunknown-pragmas]
 #pragma warning(disable : 4996)
 
bulldozer.cpp: In member function 'void P::normalize()':
bulldozer.cpp:53:23: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if (y < 0 || y == 0 && x < 0) {
                ~~~~~~~^~~~~~~~
bulldozer.cpp: In constructor 'Line::Line(P&, P&)':
bulldozer.cpp:79:23: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   if (a < 0 || a == 0 && b < 0) {
                ~~~~~~~^~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 0 / 20
• Subtask 3: 0 / 35
• Subtask 4: 0 / 20
• Subtask 5: 0 / 20