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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#679277#9520. Concave Hullucup-team5062#AC ✓154ms8256kbC++173.9kb2024-10-26 17:16:152024-10-30 01:31:21

Judging History

你现在查看的是最新测评结果

  • [2024-10-30 01:31:21]
  • 自动重测本题所有获得100分的提交记录
  • 测评结果:AC
  • 用时:154ms
  • 内存:8256kb
  • [2024-10-30 01:29:57]
  • hack成功,自动添加数据
  • (/hack/1083)
  • [2024-10-26 17:16:17]
  • 评测
  • 测评结果:100
  • 用时:157ms
  • 内存:8372kb
  • [2024-10-26 17:16:15]
  • 提交

answer

#include <string>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;

const long long INF = 15LL << 59;

string to_string(const vector<int>& arr) {
	string res = "[";
	for (int i = 0; i < int(arr.size()); i++) {
		if (i != 0) {
			res += ", ";
		}
		res += to_string(arr[i]);
	}
	res += "]";
	return res;
}

class point {
public:
	long long x, y;
	point() : x(0), y(0) {}
	point(long long x_, long long y_) : x(x_), y(y_) {}
	bool operator==(const point& p) const { return x == p.x && y == p.y; }
	bool operator!=(const point& p) const { return x != p.x || y != p.y; }
	point& operator+=(const point& p) { x += p.x; y += p.y; return *this; }
	point& operator-=(const point& p) { x -= p.x; y -= p.y; return *this; }
	point& operator*=(long long v) { x *= v; y *= v; return *this; }
	point operator+(const point& p) const { return point(*this) += p; }
	point operator-(const point& p) const { return point(*this) -= p; }
	point operator*(long long v) const { return point(*this) *= v; }
	long long dot(const point& p) const { return x * p.x + y * p.y; }
	long long cross(const point& p) const { return x * p.y - y * p.x; }
	string to_string() const {
		return "(" + std::to_string(x) + ", " + std::to_string(y) + ")";
	}
};

enum { ONLINE_FRONT = -2, CLOCKWISE, ON_SEGMENT, COUNTER_CLOCKWISE, ONLINE_BACK };
int ccw(const point& z, const point& a, const point& b) {
	if ((a - z).cross(b - z) > 0) return COUNTER_CLOCKWISE;
	if ((a - z).cross(b - z) < 0) return CLOCKWISE;
	if ((a - z).dot(b - z) < 0) return ONLINE_BACK;
	if ((z - a).dot(b - a) < 0) return ONLINE_FRONT;
	return ON_SEGMENT;
}

vector<int> convex_hull(int n, const vector<point>& g) {
	if (g == vector<point>(n, g[0])) {
		return {0};
	}
	vector<int> ord(n);
	for (int i = 0; i < n; i++) {
		ord[i] = i;
	}
	sort(ord.begin(), ord.end(), [&](int a, int b) {
		return g[a].y != g[b].y ? g[a].y < g[b].y : g[a].x < g[b].x;
	});
	vector<int> st;
	for (int i = 0; i < 2; i++) {
		int base = st.size();
		for (int v0 : ord) {
			while (int(st.size()) >= base + 2) {
				int v1 = st[st.size() - 1];
				int v2 = st[st.size() - 2];
				int z = ccw(g[v0], g[v1], g[v2]);
				if (z == CLOCKWISE) {
					break;
				}
				st.pop_back();
			}
			st.push_back(v0);
		}
		st.pop_back();
		reverse(ord.begin(), ord.end());
	}
	return st;
}

long long solve(int N, const vector<point>& P) {
	// step #1. compute first layer
	vector<int> s1 = convex_hull(N, P);
	vector<bool> used(N, false);
	for (int i : s1) {
		used[i] = true;
	}
	if (used == vector<bool>(N, true)) {
		return -1; // P is convex
	}

	// step #2. compute second layer
	vector<point> Q;
	for (int i = 0; i < N; i++) {
		if (!used[i]) {
			Q.push_back(P[i]);
		}
	}
	vector<int> s2 = convex_hull(Q.size(), Q);

	// step #3. calculate area
	s1.push_back(s1[0]);
	long long area = 0;
	for (int i = 0; i < int(s1.size()) - 1; i++) {
		area += P[s1[i]].cross(P[s1[i + 1]]);
	}

	// step #4. calculate answer
	long long mindec = INF;
	for (int i = 0; i < int(s1.size()) - 1; i++) {
		point v = P[s1[i + 1]] - P[s1[i]];
		auto comp = [&](int x, int y) {
			return v.cross(Q[s2[x]] - P[s1[i]]) > v.cross(Q[s2[y]] - P[s1[i]]);
		};
		int a = 0, b = s2.size(), c = s2.size() * 2;
		while (abs(c - a) > 2) {
			if (abs(b - a) < abs(c - b)) {
				swap(a, c);
			}
			int s = (a + b) / 2;
			if (comp(s % s2.size(), b % s2.size())) {
				a = s;
			} else {
				c = b;
				b = s;
			}
		}
		int target = b % s2.size();
		long long reduce = v.cross(Q[s2[target]] - P[s1[i]]);
		mindec = min(mindec, reduce);
	}

	return area - mindec;
}

int main() {
	int T;
	cin >> T;
	for (int id = 1; id <= T; id++) {
		int N;
		cin >> N;
		vector<point> P(N);
		for (int i = 0; i < N; i++) {
			cin >> P[i].x >> P[i].y;
		}
		long long ans = solve(N, P);
		cout << ans << '\n';
	}
	return 0;
}

这程序好像有点Bug,我给组数据试试?

详细

Test #1:

score: 100
Accepted
time: 0ms
memory: 3556kb

input:

2
6
-2 0
1 -2
5 2
0 4
1 2
3 1
4
0 0
1 0
0 1
1 1

output:

40
-1

result:

ok 2 lines

Test #2:

score: 0
Accepted
time: 1ms
memory: 3636kb

input:

10
243
-494423502 -591557038
-493438474 -648991734
-493289308 -656152126
-491185085 -661710614
-489063449 -666925265
-464265894 -709944049
-447472922 -737242534
-415977509 -773788538
-394263365 -797285016
-382728841 -807396819
-373481975 -814685302
-368242265 -818267002
-344482838 -833805545
-279398...

output:

2178418010787347715
1826413114144932145
1651687576234220014
1883871859778998985
2119126281997959892
894016174881844630
2271191316922158910
1998643358049669416
1740474221286618711
1168195646932543192

result:

ok 10 lines

Test #3:

score: 0
Accepted
time: 64ms
memory: 3936kb

input:

1000
125
64661186 -13143076
302828013 -185438065
-418713797 -191594241
430218126 -397441626
354327250 -836704374
149668812 -598584998
311305970 66790541
199720625 -592356787
468137 -584752683
258775829 96211747
-358669612 -134890109
-129221188 -998432368
-277309896 -140056561
356901185 420557649
-51...

output:

1986320445246155278
1900093336073022078
1612088392301142476
2012259136539173407
1819942017252118749
1772230185841892196
1164835025329039520
1527446155241140517
1807368432185303666
1236918659444944569
1306839249967484778
1984123720246784099
1868728080720036006
667458140583450322
2127932992585026491
4...

result:

ok 1000 lines

Test #4:

score: 0
Accepted
time: 103ms
memory: 3808kb

input:

10000
9
484630042 51929469
-40468396 -517784096
98214104 -103353239
629244333 -475172587
106398764 153884485
49211709 -44865749
1 10
166321833 -247717657
406208245 668933360
13
548702216 -631976459
37150086 -292461024
707804811 -486185860
239775286 -903166050
10096571 -541890068
686103484 558731937
...

output:

950319193795831919
1661025342421008544
1285164852091455548
1159924751776806668
1206071151805176722
794021230296144371
699991678992587791
1133990718508584290
1486311831172661605
984875884297072200
1327767982175057345
758247019006396699
1355381234262206155
1139262078529131471
1613462877860621700
12392...

result:

ok 10000 lines

Test #5:

score: 0
Accepted
time: 144ms
memory: 3844kb

input:

100
439
471536154 -312612104
155692036 -937312180
-461624056 -357636609
236656684 -911414873
-288656914 -74788431
-465779694 -381475149
-334197401 -903065737
491513067 -447615916
337664889 -852236281
-281689379 -53519178
-159101704 -920779200
-326159514 -95396204
21868593 -994282736
488425383 -41046...

output:

1973162724053130487
2054612790507830954
1726805687754843724
1699420177872986528
2129388571309147631
2198295137903288810
1697185883164440272
1219697450095721478
2027023581922285255
1674691247127206655
1673105966817209954
2179188692918747442
2146544318743443141
2230356305133660648
1676850321902993764
...

result:

ok 100 lines

Test #6:

score: 0
Accepted
time: 119ms
memory: 3868kb

input:

100
1362
-467257672 -466669
-467054869 -478108
-466973270 -481776
-466556983 -499770
-466329414 -508693
-466248017 -511805
-466158865 -513786
-466101273 -515035
-465927700 -518748
-465717624 -522106
-465303448 -528127
-465124548 -530726
-464649746 -536693
-464554872 -537799
-464478196 -538680
-46416...

output:

1666097696993497
1791366071767866
1806187278469532
1683419854733713
1685891971828916
1730190225081651
1787048201197565
1850308098208660
1710694884375502
1826363113637639
1816375352374659
2047431269497691
1549806516003854
1829438662895747
1678707854135065
1687423392883819
2121960009997761
16687219538...

result:

ok 100 lines

Test #7:

score: 0
Accepted
time: 65ms
memory: 6200kb

input:

2
62666
-486101704 -505730259
-486101698 -506082699
-486101689 -506111362
-486101682 -506126031
-486101528 -506293759
-486101259 -506556385
-486101196 -506613483
-486101154 -506648604
-486100935 -506831392
-486100631 -507083675
-486100470 -507199151
-486100233 -507368923
-486100193 -507397039
-48609...

output:

2178736946152219010
1825181940245096152

result:

ok 2 lines

Test #8:

score: 0
Accepted
time: 147ms
memory: 8256kb

input:

2
100000
301945097 76373292
467957663 -286424714
8245445 -597212507
-474204621 -708828667
184159460 105942538
443435905 -429212625
490658771 -382198656
82512047 -612522436
-228221388 -965890088
394789011 -145801151
-106120174 -528202395
428939626 -194437311
497429477 -527407728
365739746 -114818962
...

output:

2502889432701099511
2267250485735988121

result:

ok 2 lines

Test #9:

score: 0
Accepted
time: 154ms
memory: 8028kb

input:

2
100000
221128057 -975244780
-618765360 -785575858
422567455 -906331476
-988680318 -150037424
-929870145 367887908
-757813541 -652471177
291995621 -956419655
-785381507 619012026
468864522 -883270094
-588416522 808557973
859345881 511394814
988105866 153775152
216931298 -976186873
467050734 8842305...

output:

6283183114882825575
6283183188903854361

result:

ok 2 lines

Test #10:

score: 0
Accepted
time: 0ms
memory: 3796kb

input:

7
5
-1000000000 -1000000000
1000000000 -1000000000
1000000000 1000000000
1 0
-1 0
5
1000000000 1000000000
-1000000000 -1000000000
-2 0
-1 0
1 -1
6
1000000000 1000000000
-1000000000 -1000000000
-3 0
-1 0
0 -1
1 -1
4
-1000000000 -1000000000
1000000000 -1000000000
1000000000 1000000000
-1000000000 1000...

output:

4000000000000000000
7000000000
9000000001
-1
6000000002000000000
7999999998000000000
-1

result:

ok 7 lines

Extra Test:

score: 0
Extra Test Passed