답안 #56674 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
56674	2018-07-12T06:53:31 Z	gs14004	Fences (JOI18_fences)	C++17	100 / 100	172 ms	1660 KB

fences

#include <bits/stdc++.h>
using namespace std;
const int MAXN = 222;
typedef pair<double, double> pi;

double ccw(pi a, pi b, pi c){
	double dx1 = b.first - a.first;
	double dy1 = b.second - a.second;
	double dx2 = c.first - a.first;
	double dy2 = c.second - a.second;
	return dx1 * dy2 - dy1 * dx2;
}

double dot(pi a, pi b, pi c){
	double dx1 = b.first - a.first;
	double dy1 = b.second - a.second;
	double dx2 = c.first - a.first;
	double dy2 = c.second - a.second;
	return dx1 * dx2 + dy1 * dy2;
}

double pdist(pi a, pi b){
	return hypot(a.first - b.first, a.second - b.second);
}

const double eps = 1e-7;
bool line_segment_intersection(pi a, pi b, pi c, pi d){
	double k1 = ccw(a, b, c);
	double k2 = ccw(a, b, d);
	if(k1 > eps && k2 > eps) return false;
	if(k1 < -eps && k2 < -eps) return false;
	k1 = ccw(c, d, a);
	k2 = ccw(c, d, b);
	if(k1 > eps && k2 > eps) return false;
	if(k1 < -eps && k2 < -eps) return false;
	return true;
}

int n, c;
pi a[MAXN];

struct node{
	int pos, arg;
	double dist;
	bool operator<(const node &n)const{
		return dist > n.dist;
	}
};

struct seg{
	double first;
	int second, basecross;
};

vector<seg> gph[MAXN];
double dist[2][MAXN];
bool vis[2][MAXN];

double solve(int p){
	priority_queue<node> pq;
	for(int i=0; i<2; i++){
		for(int j=0; j<2*n+8; j++){
			dist[i][j] = 1e9;
			vis[i][j] = 0;
		}
	}
	dist[0][p] = 0;
	while(true){
		int sx = -1, sy = -1;
		double cur = 1e9;
		for(int i=0; i<2; i++){
			for(int j=0; j<2*n+8; j++){
				if(!vis[i][j] && dist[i][j] < cur){
					cur = dist[i][j];
					sx = i;
					sy = j;
				}
			}
		}
		if(sx == -1 || sy == -1) break;
		vis[sx][sy] = 1;
		for(auto &i : gph[sy]){
			if(dist[sx ^ i.basecross][i.second] > i.first + cur){
				dist[sx ^ i.basecross][i.second] = i.first + cur;
			}
		}
	}
	return dist[1][p];
}

bool is_cross(pi a, pi b){
	return line_segment_intersection(a, b, pi(0, 0), pi(233, 569));
}

void makeGraph(){
	auto add_edge = [&](int s, int e, double x, bool augment = false){
	//	printf("%d %d %.10f\n",s ,e , x);
		gph[s].push_back({x, e, is_cross(a[s], a[e]) ^ augment});
		gph[e].push_back({x, s, is_cross(a[s], a[e]) ^ augment});
	};
	for(int i=0; i<n+4; i++){
		add_edge(2*i, 2*i+1, 0);
	}
	add_edge(2*n, 2*n+2, 2*c);
	add_edge(2*n, 2*n+4, 2*c);
	add_edge(2*n+2, 2*n+6, 2*c);
	add_edge(2*n+4, 2*n+6, 2*c);
	for(int i=0; i<2*n+8; i++){
		for(int j=0; j<2*n; j++){
			if(j % 2 == 1) continue;
			if(i / 2 == j / 2) continue;
			pi p1 = a[i];
			pi p2 = pi(-1, -1);
			if(dot(a[j], a[j+1], p1) < 0 || dot(a[j+1], a[j], p1) < 0){
				if(pdist(a[j], p1) < pdist(a[j+1], p1)) p2 = a[j];
				else p2 = a[j+1];
			}
			else{
				double arg = ccw(a[j], a[j+1], p1) / pdist(a[j], a[j+1]);
				double dx = (a[j+1].first - a[j].first) / pdist(a[j], a[j+1]);
				double dy = (a[j+1].second - a[j].second) / pdist(a[j], a[j+1]);
				p2 = p1;
				p2.first += dy * arg;
				p2.second -= dx * arg;
			}
			if(i == 2 * n || i == 2 * n + 1){
				if(p2.first <= -c || p2.second <= -c) {
					add_edge(i, j, pdist(p1, p2), is_cross(a[i], a[j]) ^ is_cross(p1, p2) ^ is_cross(p2, a[j]));
				}
				else continue;
			}
			if(i == 2 * n + 2 || i == 2 * n + 3){
				if(p2.first <= -c || p2.second >= c){
					add_edge(i, j, pdist(p1, p2), is_cross(a[i], a[j]) ^ is_cross(p1, p2) ^ is_cross(p2, a[j]));
				}
				else continue;
			}
			if(i == 2 * n + 4 || i == 2 * n + 5){
				if(p2.first >= c || p2.second <= -c){
					add_edge(i, j, pdist(p1, p2), is_cross(a[i], a[j]) ^ is_cross(p1, p2) ^ is_cross(p2, a[j]));
				}
				else continue;
			}
			if(i == 2 * n + 6 || i == 2 * n + 7){
				if(p2.first >= c || p2.second >= c){
					add_edge(i, j, pdist(p1, p2), is_cross(a[i], a[j]) ^ is_cross(p1, p2) ^ is_cross(p2, a[j]));
				}
				else continue;
			}
			double lx = -c, rx = c;
			if(line_segment_intersection(p1, p2, pi(lx, rx), pi(lx, lx))) continue;
			if(line_segment_intersection(p1, p2, pi(lx, rx), pi(rx, rx))) continue;
			if(line_segment_intersection(p1, p2, pi(rx, rx), pi(rx, lx))) continue;
			if(line_segment_intersection(p1, p2, pi(rx, lx), pi(lx, lx))) continue;
			add_edge(i, j, pdist(p1, p2), is_cross(a[i], a[j]) ^ is_cross(p1, p2) ^ is_cross(p2, a[j]));
		}
	}
}

int main(){
	cin >> n >> c;
	for(int i=0; i<2*n; i++){
		cin >> a[i].first >> a[i].second;
	}
	a[2*n+0] = a[2*n+1] = pi(-c, -c);
	a[2*n+2] = a[2*n+3] = pi(-c, c);
	a[2*n+4] = a[2*n+5] = pi(c, -c);
	a[2*n+6] = a[2*n+7] = pi(c, c);
	makeGraph();
	double ans = 1e9;
	for(int i=0; i<2*n+8; i++) ans = min(ans, solve(i));
	printf("%.10f\n", ans);
}

Subtask #1
18.0 / 18.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	376 KB	Output is correct
2	Correct	3 ms	468 KB	Output is correct
3	Correct	2 ms	468 KB	Output is correct
4	Correct	2 ms	472 KB	Output is correct
5	Correct	2 ms	496 KB	Output is correct
6	Correct	3 ms	496 KB	Output is correct
7	Correct	2 ms	572 KB	Output is correct
8	Correct	2 ms	572 KB	Output is correct
9	Correct	2 ms	620 KB	Output is correct
10	Correct	2 ms	620 KB	Output is correct
11	Correct	2 ms	624 KB	Output is correct
12	Correct	2 ms	624 KB	Output is correct
13	Correct	3 ms	624 KB	Output is correct
14	Correct	2 ms	624 KB	Output is correct
15	Correct	2 ms	624 KB	Output is correct
16	Correct	2 ms	748 KB	Output is correct
17	Correct	2 ms	748 KB	Output is correct
18	Correct	2 ms	748 KB	Output is correct
19	Correct	3 ms	748 KB	Output is correct
20	Correct	2 ms	748 KB	Output is correct

Subtask #2
33.0 / 33.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	376 KB	Output is correct
2	Correct	3 ms	468 KB	Output is correct
3	Correct	2 ms	468 KB	Output is correct
4	Correct	2 ms	472 KB	Output is correct
5	Correct	2 ms	496 KB	Output is correct
6	Correct	3 ms	496 KB	Output is correct
7	Correct	2 ms	572 KB	Output is correct
8	Correct	2 ms	572 KB	Output is correct
9	Correct	2 ms	620 KB	Output is correct
10	Correct	2 ms	620 KB	Output is correct
11	Correct	2 ms	624 KB	Output is correct
12	Correct	2 ms	624 KB	Output is correct
13	Correct	3 ms	624 KB	Output is correct
14	Correct	2 ms	624 KB	Output is correct
15	Correct	2 ms	624 KB	Output is correct
16	Correct	2 ms	748 KB	Output is correct
17	Correct	2 ms	748 KB	Output is correct
18	Correct	2 ms	748 KB	Output is correct
19	Correct	3 ms	748 KB	Output is correct
20	Correct	2 ms	748 KB	Output is correct
21	Correct	2 ms	748 KB	Output is correct
22	Correct	2 ms	748 KB	Output is correct
23	Correct	3 ms	748 KB	Output is correct
24	Correct	2 ms	748 KB	Output is correct
25	Correct	2 ms	748 KB	Output is correct
26	Correct	3 ms	752 KB	Output is correct
27	Correct	3 ms	752 KB	Output is correct
28	Correct	2 ms	752 KB	Output is correct
29	Correct	0 ms	752 KB	Output is correct
30	Correct	2 ms	752 KB	Output is correct
31	Correct	3 ms	752 KB	Output is correct
32	Correct	3 ms	752 KB	Output is correct
33	Correct	2 ms	752 KB	Output is correct
34	Correct	2 ms	752 KB	Output is correct
35	Correct	2 ms	752 KB	Output is correct
36	Correct	4 ms	752 KB	Output is correct
37	Correct	2 ms	752 KB	Output is correct
38	Correct	2 ms	752 KB	Output is correct
39	Correct	2 ms	752 KB	Output is correct
40	Correct	2 ms	752 KB	Output is correct
41	Correct	2 ms	752 KB	Output is correct
42	Correct	3 ms	752 KB	Output is correct
43	Correct	2 ms	752 KB	Output is correct

Subtask #3
49.0 / 49.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	376 KB	Output is correct
2	Correct	3 ms	468 KB	Output is correct
3	Correct	2 ms	468 KB	Output is correct
4	Correct	2 ms	472 KB	Output is correct
5	Correct	2 ms	496 KB	Output is correct
6	Correct	3 ms	496 KB	Output is correct
7	Correct	2 ms	572 KB	Output is correct
8	Correct	2 ms	572 KB	Output is correct
9	Correct	2 ms	620 KB	Output is correct
10	Correct	2 ms	620 KB	Output is correct
11	Correct	2 ms	624 KB	Output is correct
12	Correct	2 ms	624 KB	Output is correct
13	Correct	3 ms	624 KB	Output is correct
14	Correct	2 ms	624 KB	Output is correct
15	Correct	2 ms	624 KB	Output is correct
16	Correct	2 ms	748 KB	Output is correct
17	Correct	2 ms	748 KB	Output is correct
18	Correct	2 ms	748 KB	Output is correct
19	Correct	3 ms	748 KB	Output is correct
20	Correct	2 ms	748 KB	Output is correct
21	Correct	2 ms	748 KB	Output is correct
22	Correct	2 ms	748 KB	Output is correct
23	Correct	3 ms	748 KB	Output is correct
24	Correct	2 ms	748 KB	Output is correct
25	Correct	2 ms	748 KB	Output is correct
26	Correct	3 ms	752 KB	Output is correct
27	Correct	3 ms	752 KB	Output is correct
28	Correct	2 ms	752 KB	Output is correct
29	Correct	0 ms	752 KB	Output is correct
30	Correct	2 ms	752 KB	Output is correct
31	Correct	3 ms	752 KB	Output is correct
32	Correct	3 ms	752 KB	Output is correct
33	Correct	2 ms	752 KB	Output is correct
34	Correct	2 ms	752 KB	Output is correct
35	Correct	2 ms	752 KB	Output is correct
36	Correct	4 ms	752 KB	Output is correct
37	Correct	2 ms	752 KB	Output is correct
38	Correct	2 ms	752 KB	Output is correct
39	Correct	2 ms	752 KB	Output is correct
40	Correct	2 ms	752 KB	Output is correct
41	Correct	2 ms	752 KB	Output is correct
42	Correct	3 ms	752 KB	Output is correct
43	Correct	2 ms	752 KB	Output is correct
44	Correct	138 ms	1660 KB	Output is correct
45	Correct	119 ms	1660 KB	Output is correct
46	Correct	111 ms	1660 KB	Output is correct
47	Correct	113 ms	1660 KB	Output is correct
48	Correct	141 ms	1660 KB	Output is correct
49	Correct	132 ms	1660 KB	Output is correct
50	Correct	128 ms	1660 KB	Output is correct
51	Correct	115 ms	1660 KB	Output is correct
52	Correct	123 ms	1660 KB	Output is correct
53	Correct	127 ms	1660 KB	Output is correct
54	Correct	139 ms	1660 KB	Output is correct
55	Correct	117 ms	1660 KB	Output is correct
56	Correct	127 ms	1660 KB	Output is correct
57	Correct	121 ms	1660 KB	Output is correct
58	Correct	172 ms	1660 KB	Output is correct
59	Correct	131 ms	1660 KB	Output is correct
60	Correct	159 ms	1660 KB	Output is correct
61	Correct	123 ms	1660 KB	Output is correct
62	Correct	2 ms	1660 KB	Output is correct
63	Correct	2 ms	1660 KB	Output is correct
64	Correct	83 ms	1660 KB	Output is correct
65	Correct	83 ms	1660 KB	Output is correct
66	Correct	66 ms	1660 KB	Output is correct
67	Correct	104 ms	1660 KB	Output is correct
68	Correct	105 ms	1660 KB	Output is correct
69	Correct	137 ms	1660 KB	Output is correct
70	Correct	133 ms	1660 KB	Output is correct
71	Correct	114 ms	1660 KB	Output is correct
72	Correct	121 ms	1660 KB	Output is correct

답안 #56674

Compilation message

Subtask #1 18.0 / 18.0

Subtask #2 33.0 / 33.0

Subtask #3 49.0 / 49.0

Subtask #1
18.0 / 18.0

Subtask #2
33.0 / 33.0

Subtask #3
49.0 / 49.0