답안 #132018

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
132018 2019-07-18T08:06:29 Z 이온조(#3189) Fences (JOI18_fences) C++14
51 / 100
1000 ms 47340 KB
#pragma GCC optimize ("Ofast")
#include <bits/stdc++.h>
using namespace std;
using pii = pair<int, int>;
using pid = pair<int, double>;
using pdi = pair<double, int>;
using pdd = pair<double, double>;
#define X first
#define Y second

const double eps = 1e-6;

struct line { pdd S, E; };
struct dot { pdd D; int id; bool ps; };
struct node { double v; int c, id; };

bool operator <(node PP, node QQ) { return PP.v > QQ.v; }

inline double f(double x) { return max(x, -x); }
inline double dst(pdd A, pdd B) { return sqrt((A.X-B.X) * (A.X-B.X) + (A.Y-B.Y) * (A.Y-B.Y)); }
inline double CCW(pdd A, pdd B, pdd C) { return A.X*B.Y + B.X*C.Y + C.X*A.Y - A.Y*B.X - B.Y*C.X - C.Y*A.X; }
inline int CCWs(pdd A, pdd B, pdd C) {
	int tmp = CCW(A, B, C);
	if(tmp < 0) return -1;
	if(tmp > 0) return +1;
	if(tmp == 0) return 0;
}
inline bool on(line A, pdd B) {
	if(A.S > A.E) swap(A.S, A.E);
	if(B < A.S || A.E < B) return false;
	return f(CCW(A.S, A.E, B)) < eps;
}
inline bool its(line A, line B) { // strict
	if(on(A, B.S) || on(A, B.E) || on(B, A.S) || on(B, A.E)) return false;
	return CCWs(A.S, A.E, B.S) * CCWs(A.S, A.E, B.E) == -1 && CCWs(B.S, B.E, A.S) * CCWs(B.S, B.E, A.E) == -1;
}
inline pdd push(line A, pdd B) {
	double ds = dst(A.S, A.E);
	double d = f(CCW(A.S, A.E, B) / ds);
	double dx = A.S.Y - A.E.Y, dy = A.E.X - A.S.X;
	pdd PA = {B.X + dx * (d/ds), B.Y + dy * (d/ds)};
	pdd PB = {B.X - dx * (d/ds), B.Y - dy * (d/ds)};
	if(dst(PA, A.S) > dst(PB, A.S)) swap(PA, PB);
	return PA;
}

line I = {{0.0, 0.0}, {1000.0, 1.0}};
vector<dot> T;
vector<pid> adj[1000009];
line A[111];
int N, S, K;
double ans = 1e9, D[2][1000009];

inline bool ok(line L) {
	bool f = 0;
	f |= its(L, {{S, S}, {-S, -S}});
	f |= its(L, {{-S, S}, {S, -S}});
	return !f;
}

void dijk(int st) {
	// printf("start: (%d, %d)\n", T[st].D.X, T[st].D.Y);
	vector<pii> rec = {{0, st}};
	D[0][st] = 0.0;
	priority_queue<node> pq; pq.push({0.0, 0, st});
	while(pq.size()) {
		node n = pq.top(); pq.pop();
		if((n.id == st && n.c == 1) || n.v > ans) break;
		// printf("now: (%f, %d, (%d, %d))\n", n.v, n.c, T[n.id].D.X, T[n.id].D.Y);
		if(f(D[n.c][n.id] - n.v) > eps) continue;
		for(auto& it: adj[n.id]) {
			int tc = n.c;
			if(its({T[n.id].D, T[it.X].D}, I)) tc = 1 - tc;
			if(D[tc][it.X] > n.v + it.Y) {
				D[tc][it.X] = n.v + it.Y;
				rec.push_back({tc, it.X});
				pq.push({D[tc][it.X], tc, it.X});
			}
		}
	}
	ans = min(ans, D[1][st]);
	for(auto& it: rec) D[it.X][it.Y] = 1e9;
}

void make_edge(int u, int v, double c) {
	adj[u].push_back({v, c});
	adj[v].push_back({u, c});
}

int main() {
	scanf("%d%d",&N,&S);
	// N = 100; S = 100;
	ans = 8.0*S;
	for(int i=1; i<=N; i++) {
		scanf("%lf%lf%lf%lf", &A[i].S.X, &A[i].S.Y, &A[i].E.X, &A[i].E.Y);
		// A[i].S = {i, 100}; A[i].E = {i+1, 100};
		T.push_back({A[i].S, i, 0});
		T.push_back({A[i].E, i, 0});
	}
	T.push_back({{S, S}, N+1, 0});
	T.push_back({{S, -S}, N+2, 0});
	T.push_back({{-S, -S}, N+3, 0});
	T.push_back({{-S, S}, N+4, 0});

	int L = T.size();

	for(int i=1; i<=N; i++) {
		for(int j=0; j<T.size(); j++) {
			if(i == T[j].id) continue;
			pdd pu = push(A[i], T[j].D);
			bool f = (ok({T[j].D, pu}) && on(A[i], pu));
			for(int k=1; k<=N && f; k++) f &= !its({pu, T[j].D}, A[k]);
			if(f) {
				// puts("ok");
				int u = T.size();
				T.push_back({pu, i, 1});
				make_edge(u, j, dst(pu, T[j].D));
				make_edge(u, 2*i-2, 0);
			}
			// else puts("not ok");
		}
	}

	K = T.size();

	// printf("K: %d\n", K);
	// for(auto& it: T) {
	// 	printf("position(%f, %f), id: %d, pushed?: %d\n", it.D.X, it.D.Y, it.id, it.ps);
	// }

	for(int i=0; i<L; i++) {
		for(int j=i+1; j<L; j++) {
			if(!ok({T[i].D, T[j].D})) continue;
			bool f = 1;
			for(int k=1; k<=N && f; k++) f &= !its({T[i].D, T[j].D}, A[k]);
			if(!f) continue;
			double d;
			if(T[i].id == T[j].id) d = 0;
			else d = dst(T[i].D, T[j].D);
			// printf("(%f, %f) <----> (%f, %f), cost: %f\n", T[i].D.X, T[i].D.Y, T[j].D.X, T[j].D.Y, d);
			adj[i].push_back({j, d});
			adj[j].push_back({i, d});
		}
	}

	for(int i=0; i<K; i++) D[0][i] = D[1][i] = 1e9;
	for(int i=0; i<2*N; i+=2) dijk(i);
	for(int i=2*N; i<2*N+4; i++) dijk(i);
	printf("%.10f", ans);
	return 0;
}

Compilation message

fences.cpp: In function 'int main()':
fences.cpp:108:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0; j<T.size(); j++) {
                ~^~~~~~~~~
fences.cpp: In function 'int CCWs(pdd, pdd, pdd)':
fences.cpp:27:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
fences.cpp: In function 'int main()':
fences.cpp:91:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&N,&S);
  ~~~~~^~~~~~~~~~~~~~
fences.cpp:95:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%lf%lf%lf%lf", &A[i].S.X, &A[i].S.Y, &A[i].E.X, &A[i].E.Y);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 25 ms 23928 KB Output is correct
2 Correct 25 ms 23800 KB Output is correct
3 Correct 25 ms 23800 KB Output is correct
4 Correct 25 ms 23800 KB Output is correct
5 Correct 26 ms 23800 KB Output is correct
6 Correct 25 ms 23800 KB Output is correct
7 Correct 25 ms 23804 KB Output is correct
8 Correct 25 ms 23800 KB Output is correct
9 Correct 25 ms 23800 KB Output is correct
10 Correct 26 ms 23828 KB Output is correct
11 Correct 25 ms 23800 KB Output is correct
12 Correct 28 ms 23848 KB Output is correct
13 Correct 25 ms 23776 KB Output is correct
14 Correct 30 ms 23804 KB Output is correct
15 Correct 28 ms 23928 KB Output is correct
16 Correct 26 ms 23928 KB Output is correct
17 Correct 25 ms 23736 KB Output is correct
18 Correct 25 ms 23800 KB Output is correct
19 Correct 25 ms 23800 KB Output is correct
20 Correct 25 ms 23800 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 25 ms 23928 KB Output is correct
2 Correct 25 ms 23800 KB Output is correct
3 Correct 25 ms 23800 KB Output is correct
4 Correct 25 ms 23800 KB Output is correct
5 Correct 26 ms 23800 KB Output is correct
6 Correct 25 ms 23800 KB Output is correct
7 Correct 25 ms 23804 KB Output is correct
8 Correct 25 ms 23800 KB Output is correct
9 Correct 25 ms 23800 KB Output is correct
10 Correct 26 ms 23828 KB Output is correct
11 Correct 25 ms 23800 KB Output is correct
12 Correct 28 ms 23848 KB Output is correct
13 Correct 25 ms 23776 KB Output is correct
14 Correct 30 ms 23804 KB Output is correct
15 Correct 28 ms 23928 KB Output is correct
16 Correct 26 ms 23928 KB Output is correct
17 Correct 25 ms 23736 KB Output is correct
18 Correct 25 ms 23800 KB Output is correct
19 Correct 25 ms 23800 KB Output is correct
20 Correct 25 ms 23800 KB Output is correct
21 Correct 25 ms 23800 KB Output is correct
22 Correct 26 ms 23800 KB Output is correct
23 Correct 26 ms 23928 KB Output is correct
24 Correct 25 ms 23748 KB Output is correct
25 Correct 24 ms 23800 KB Output is correct
26 Correct 25 ms 23804 KB Output is correct
27 Correct 26 ms 23800 KB Output is correct
28 Correct 26 ms 23772 KB Output is correct
29 Correct 26 ms 23784 KB Output is correct
30 Correct 25 ms 23804 KB Output is correct
31 Correct 25 ms 23804 KB Output is correct
32 Correct 25 ms 23928 KB Output is correct
33 Correct 25 ms 23800 KB Output is correct
34 Correct 25 ms 23800 KB Output is correct
35 Correct 25 ms 23800 KB Output is correct
36 Correct 27 ms 23800 KB Output is correct
37 Correct 25 ms 23800 KB Output is correct
38 Correct 25 ms 23800 KB Output is correct
39 Correct 26 ms 23800 KB Output is correct
40 Correct 25 ms 23800 KB Output is correct
41 Correct 23 ms 23800 KB Output is correct
42 Correct 26 ms 23800 KB Output is correct
43 Correct 25 ms 23800 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 25 ms 23928 KB Output is correct
2 Correct 25 ms 23800 KB Output is correct
3 Correct 25 ms 23800 KB Output is correct
4 Correct 25 ms 23800 KB Output is correct
5 Correct 26 ms 23800 KB Output is correct
6 Correct 25 ms 23800 KB Output is correct
7 Correct 25 ms 23804 KB Output is correct
8 Correct 25 ms 23800 KB Output is correct
9 Correct 25 ms 23800 KB Output is correct
10 Correct 26 ms 23828 KB Output is correct
11 Correct 25 ms 23800 KB Output is correct
12 Correct 28 ms 23848 KB Output is correct
13 Correct 25 ms 23776 KB Output is correct
14 Correct 30 ms 23804 KB Output is correct
15 Correct 28 ms 23928 KB Output is correct
16 Correct 26 ms 23928 KB Output is correct
17 Correct 25 ms 23736 KB Output is correct
18 Correct 25 ms 23800 KB Output is correct
19 Correct 25 ms 23800 KB Output is correct
20 Correct 25 ms 23800 KB Output is correct
21 Correct 25 ms 23800 KB Output is correct
22 Correct 26 ms 23800 KB Output is correct
23 Correct 26 ms 23928 KB Output is correct
24 Correct 25 ms 23748 KB Output is correct
25 Correct 24 ms 23800 KB Output is correct
26 Correct 25 ms 23804 KB Output is correct
27 Correct 26 ms 23800 KB Output is correct
28 Correct 26 ms 23772 KB Output is correct
29 Correct 26 ms 23784 KB Output is correct
30 Correct 25 ms 23804 KB Output is correct
31 Correct 25 ms 23804 KB Output is correct
32 Correct 25 ms 23928 KB Output is correct
33 Correct 25 ms 23800 KB Output is correct
34 Correct 25 ms 23800 KB Output is correct
35 Correct 25 ms 23800 KB Output is correct
36 Correct 27 ms 23800 KB Output is correct
37 Correct 25 ms 23800 KB Output is correct
38 Correct 25 ms 23800 KB Output is correct
39 Correct 26 ms 23800 KB Output is correct
40 Correct 25 ms 23800 KB Output is correct
41 Correct 23 ms 23800 KB Output is correct
42 Correct 26 ms 23800 KB Output is correct
43 Correct 25 ms 23800 KB Output is correct
44 Correct 86 ms 24236 KB Output is correct
45 Correct 134 ms 24300 KB Output is correct
46 Correct 177 ms 24472 KB Output is correct
47 Correct 150 ms 24288 KB Output is correct
48 Correct 89 ms 24184 KB Output is correct
49 Correct 136 ms 24388 KB Output is correct
50 Correct 152 ms 24240 KB Output is correct
51 Correct 140 ms 24188 KB Output is correct
52 Correct 148 ms 24264 KB Output is correct
53 Correct 123 ms 24348 KB Output is correct
54 Correct 111 ms 24216 KB Output is correct
55 Correct 136 ms 24308 KB Output is correct
56 Correct 148 ms 24240 KB Output is correct
57 Correct 153 ms 24232 KB Output is correct
58 Correct 170 ms 24280 KB Output is correct
59 Correct 140 ms 24220 KB Output is correct
60 Correct 152 ms 24272 KB Output is correct
61 Correct 133 ms 24268 KB Output is correct
62 Correct 26 ms 23800 KB Output is correct
63 Correct 26 ms 23800 KB Output is correct
64 Correct 142 ms 24420 KB Output is correct
65 Correct 224 ms 24680 KB Output is correct
66 Correct 179 ms 24668 KB Output is correct
67 Execution timed out 1040 ms 47340 KB Time limit exceeded
68 Halted 0 ms 0 KB -