oj.uz

답안 #132025

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
132025 2019-07-18T08:14:19 Z 이온조(#3189) Fences (JOI18_fences) C++14
51 / 100
 1000 ms 61024 KB 
#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) {
	double tmp = CCW(A, B, C);
	if(f(tmp) < eps) return 0;
	if(tmp < 0) return -1;
	if(tmp > 0) return +1;
}
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
	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];
bool IT[40009][40009];

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(IT[n.id][it.X]) 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();

	for(int i=0; i<K; i++) {
		for(int j=i+1; j<K; j++) {
			if(its({T[i].D, T[j].D}, I)) IT[i][j] = IT[j][i] = 1;
		}
	}

	// 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:107:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0; j<T.size(); j++) {
                ~^~~~~~~~~
fences.cpp:90:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&N,&S);
  ~~~~~^~~~~~~~~~~~~~
fences.cpp:94:8: 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);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fences.cpp: In function 'int CCWs(pdd, pdd, pdd)':
fences.cpp:26:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

Subtask #1
18.0 / 18.0

# 결과 실행 시간 메모리 Grader output
1 Correct 26 ms 23800 KB Output is correct
2 Correct 24 ms 23800 KB Output is correct
3 Correct 24 ms 23800 KB Output is correct
4 Correct 24 ms 23800 KB Output is correct
5 Correct 24 ms 23800 KB Output is correct
6 Correct 23 ms 23928 KB Output is correct
7 Correct 23 ms 23928 KB Output is correct
8 Correct 24 ms 23800 KB Output is correct
9 Correct 24 ms 23800 KB Output is correct
10 Correct 24 ms 23844 KB Output is correct
11 Correct 24 ms 23800 KB Output is correct
12 Correct 24 ms 23928 KB Output is correct
13 Correct 23 ms 23804 KB Output is correct
14 Correct 24 ms 23800 KB Output is correct
15 Correct 24 ms 23800 KB Output is correct
16 Correct 23 ms 23800 KB Output is correct
17 Correct 23 ms 23800 KB Output is correct
18 Correct 24 ms 23928 KB Output is correct
19 Correct 24 ms 23772 KB Output is correct
20 Correct 24 ms 23800 KB Output is correct

Subtask #2
33.0 / 33.0

# 결과 실행 시간 메모리 Grader output
1 Correct 26 ms 23800 KB Output is correct
2 Correct 24 ms 23800 KB Output is correct
3 Correct 24 ms 23800 KB Output is correct
4 Correct 24 ms 23800 KB Output is correct
5 Correct 24 ms 23800 KB Output is correct
6 Correct 23 ms 23928 KB Output is correct
7 Correct 23 ms 23928 KB Output is correct
8 Correct 24 ms 23800 KB Output is correct
9 Correct 24 ms 23800 KB Output is correct
10 Correct 24 ms 23844 KB Output is correct
11 Correct 24 ms 23800 KB Output is correct
12 Correct 24 ms 23928 KB Output is correct
13 Correct 23 ms 23804 KB Output is correct
14 Correct 24 ms 23800 KB Output is correct
15 Correct 24 ms 23800 KB Output is correct
16 Correct 23 ms 23800 KB Output is correct
17 Correct 23 ms 23800 KB Output is correct
18 Correct 24 ms 23928 KB Output is correct
19 Correct 24 ms 23772 KB Output is correct
20 Correct 24 ms 23800 KB Output is correct
21 Correct 24 ms 23928 KB Output is correct
22 Correct 27 ms 24028 KB Output is correct
23 Correct 24 ms 23928 KB Output is correct
24 Correct 27 ms 23928 KB Output is correct
25 Correct 24 ms 23928 KB Output is correct
26 Correct 24 ms 23928 KB Output is correct
27 Correct 25 ms 23928 KB Output is correct
28 Correct 30 ms 23900 KB Output is correct
29 Correct 24 ms 23928 KB Output is correct
30 Correct 24 ms 23928 KB Output is correct
31 Correct 24 ms 23928 KB Output is correct
32 Correct 25 ms 23928 KB Output is correct
33 Correct 24 ms 23928 KB Output is correct
34 Correct 25 ms 23928 KB Output is correct
35 Correct 24 ms 24056 KB Output is correct
36 Correct 24 ms 24056 KB Output is correct
37 Correct 24 ms 23928 KB Output is correct
38 Correct 24 ms 23800 KB Output is correct
39 Correct 24 ms 24056 KB Output is correct
40 Correct 23 ms 23928 KB Output is correct
41 Correct 24 ms 23928 KB Output is correct
42 Correct 24 ms 24108 KB Output is correct
43 Correct 25 ms 24508 KB Output is correct

Subtask #3
0 / 49.0

# 결과 실행 시간 메모리 Grader output
1 Correct 26 ms 23800 KB Output is correct
2 Correct 24 ms 23800 KB Output is correct
3 Correct 24 ms 23800 KB Output is correct
4 Correct 24 ms 23800 KB Output is correct
5 Correct 24 ms 23800 KB Output is correct
6 Correct 23 ms 23928 KB Output is correct
7 Correct 23 ms 23928 KB Output is correct
8 Correct 24 ms 23800 KB Output is correct
9 Correct 24 ms 23800 KB Output is correct
10 Correct 24 ms 23844 KB Output is correct
11 Correct 24 ms 23800 KB Output is correct
12 Correct 24 ms 23928 KB Output is correct
13 Correct 23 ms 23804 KB Output is correct
14 Correct 24 ms 23800 KB Output is correct
15 Correct 24 ms 23800 KB Output is correct
16 Correct 23 ms 23800 KB Output is correct
17 Correct 23 ms 23800 KB Output is correct
18 Correct 24 ms 23928 KB Output is correct
19 Correct 24 ms 23772 KB Output is correct
20 Correct 24 ms 23800 KB Output is correct
21 Correct 24 ms 23928 KB Output is correct
22 Correct 27 ms 24028 KB Output is correct
23 Correct 24 ms 23928 KB Output is correct
24 Correct 27 ms 23928 KB Output is correct
25 Correct 24 ms 23928 KB Output is correct
26 Correct 24 ms 23928 KB Output is correct
27 Correct 25 ms 23928 KB Output is correct
28 Correct 30 ms 23900 KB Output is correct
29 Correct 24 ms 23928 KB Output is correct
30 Correct 24 ms 23928 KB Output is correct
31 Correct 24 ms 23928 KB Output is correct
32 Correct 25 ms 23928 KB Output is correct
33 Correct 24 ms 23928 KB Output is correct
34 Correct 25 ms 23928 KB Output is correct
35 Correct 24 ms 24056 KB Output is correct
36 Correct 24 ms 24056 KB Output is correct
37 Correct 24 ms 23928 KB Output is correct
38 Correct 24 ms 23800 KB Output is correct
39 Correct 24 ms 24056 KB Output is correct
40 Correct 23 ms 23928 KB Output is correct
41 Correct 24 ms 23928 KB Output is correct
42 Correct 24 ms 24108 KB Output is correct
43 Correct 25 ms 24508 KB Output is correct
44 Correct 91 ms 33528 KB Output is correct
45 Correct 126 ms 33188 KB Output is correct
46 Correct 164 ms 34436 KB Output is correct
47 Correct 110 ms 29640 KB Output is correct
48 Correct 88 ms 32248 KB Output is correct
49 Correct 121 ms 32720 KB Output is correct
50 Correct 127 ms 30888 KB Output is correct
51 Correct 112 ms 29752 KB Output is correct
52 Correct 120 ms 30868 KB Output is correct
53 Correct 110 ms 31360 KB Output is correct
54 Correct 97 ms 30664 KB Output is correct
55 Correct 113 ms 30528 KB Output is correct
56 Correct 132 ms 32188 KB Output is correct
57 Correct 130 ms 31300 KB Output is correct
58 Correct 153 ms 33064 KB Output is correct
59 Correct 120 ms 31132 KB Output is correct
60 Correct 130 ms 31508 KB Output is correct
61 Correct 118 ms 31956 KB Output is correct
62 Correct 24 ms 24056 KB Output is correct
63 Correct 25 ms 24312 KB Output is correct
64 Correct 116 ms 29304 KB Output is correct
65 Correct 130 ms 25492 KB Output is correct
66 Correct 113 ms 25348 KB Output is correct
67 Execution timed out 1082 ms 61024 KB Time limit exceeded
68 Halted 0 ms 0 KB -