oj.uz

Submission #132022

# Submission time Handle Problem Language Result Execution time Memory
132022 2019-07-18T08:10:20 Z 이온조(#3189) Fences (JOI18_fences) C++14
51 / 100
 1000 ms 49560 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];
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:109:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j=0; j<T.size(); j++) {
                ~^~~~~~~~~
fences.cpp:92:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&N,&S);
  ~~~~~^~~~~~~~~~~~~~
fences.cpp:96:8: 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:27:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 23800 KB Output is correct
2 Correct 26 ms 23896 KB Output is correct
3 Correct 25 ms 23800 KB Output is correct
4 Correct 25 ms 23800 KB Output is correct
5 Correct 25 ms 23800 KB Output is correct
6 Correct 26 ms 23800 KB Output is correct
7 Correct 26 ms 23928 KB Output is correct
8 Correct 25 ms 23800 KB Output is correct
9 Correct 26 ms 23800 KB Output is correct
10 Correct 25 ms 23788 KB Output is correct
11 Correct 25 ms 23800 KB Output is correct
12 Correct 25 ms 23928 KB Output is correct
13 Correct 25 ms 23800 KB Output is correct
14 Correct 25 ms 23928 KB Output is correct
15 Correct 25 ms 23928 KB Output is correct
16 Correct 25 ms 23928 KB Output is correct
17 Correct 25 ms 23928 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

Subtask #2
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 23800 KB Output is correct
2 Correct 26 ms 23896 KB Output is correct
3 Correct 25 ms 23800 KB Output is correct
4 Correct 25 ms 23800 KB Output is correct
5 Correct 25 ms 23800 KB Output is correct
6 Correct 26 ms 23800 KB Output is correct
7 Correct 26 ms 23928 KB Output is correct
8 Correct 25 ms 23800 KB Output is correct
9 Correct 26 ms 23800 KB Output is correct
10 Correct 25 ms 23788 KB Output is correct
11 Correct 25 ms 23800 KB Output is correct
12 Correct 25 ms 23928 KB Output is correct
13 Correct 25 ms 23800 KB Output is correct
14 Correct 25 ms 23928 KB Output is correct
15 Correct 25 ms 23928 KB Output is correct
16 Correct 25 ms 23928 KB Output is correct
17 Correct 25 ms 23928 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 25 ms 24056 KB Output is correct
23 Correct 25 ms 23928 KB Output is correct
24 Correct 26 ms 23928 KB Output is correct
25 Correct 25 ms 23928 KB Output is correct
26 Correct 26 ms 23928 KB Output is correct
27 Correct 25 ms 23928 KB Output is correct
28 Correct 25 ms 23932 KB Output is correct
29 Correct 25 ms 23928 KB Output is correct
30 Correct 26 ms 23928 KB Output is correct
31 Correct 28 ms 23928 KB Output is correct
32 Correct 30 ms 23928 KB Output is correct
33 Correct 26 ms 23928 KB Output is correct
34 Correct 26 ms 23928 KB Output is correct
35 Correct 26 ms 24056 KB Output is correct
36 Correct 26 ms 24056 KB Output is correct
37 Correct 25 ms 23928 KB Output is correct
38 Correct 26 ms 23800 KB Output is correct
39 Correct 26 ms 23928 KB Output is correct
40 Correct 25 ms 23932 KB Output is correct
41 Correct 25 ms 23800 KB Output is correct
42 Correct 26 ms 24056 KB Output is correct
43 Correct 26 ms 24568 KB Output is correct

Subtask #3
0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 23800 KB Output is correct
2 Correct 26 ms 23896 KB Output is correct
3 Correct 25 ms 23800 KB Output is correct
4 Correct 25 ms 23800 KB Output is correct
5 Correct 25 ms 23800 KB Output is correct
6 Correct 26 ms 23800 KB Output is correct
7 Correct 26 ms 23928 KB Output is correct
8 Correct 25 ms 23800 KB Output is correct
9 Correct 26 ms 23800 KB Output is correct
10 Correct 25 ms 23788 KB Output is correct
11 Correct 25 ms 23800 KB Output is correct
12 Correct 25 ms 23928 KB Output is correct
13 Correct 25 ms 23800 KB Output is correct
14 Correct 25 ms 23928 KB Output is correct
15 Correct 25 ms 23928 KB Output is correct
16 Correct 25 ms 23928 KB Output is correct
17 Correct 25 ms 23928 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 25 ms 24056 KB Output is correct
23 Correct 25 ms 23928 KB Output is correct
24 Correct 26 ms 23928 KB Output is correct
25 Correct 25 ms 23928 KB Output is correct
26 Correct 26 ms 23928 KB Output is correct
27 Correct 25 ms 23928 KB Output is correct
28 Correct 25 ms 23932 KB Output is correct
29 Correct 25 ms 23928 KB Output is correct
30 Correct 26 ms 23928 KB Output is correct
31 Correct 28 ms 23928 KB Output is correct
32 Correct 30 ms 23928 KB Output is correct
33 Correct 26 ms 23928 KB Output is correct
34 Correct 26 ms 23928 KB Output is correct
35 Correct 26 ms 24056 KB Output is correct
36 Correct 26 ms 24056 KB Output is correct
37 Correct 25 ms 23928 KB Output is correct
38 Correct 26 ms 23800 KB Output is correct
39 Correct 26 ms 23928 KB Output is correct
40 Correct 25 ms 23932 KB Output is correct
41 Correct 25 ms 23800 KB Output is correct
42 Correct 26 ms 24056 KB Output is correct
43 Correct 26 ms 24568 KB Output is correct
44 Correct 113 ms 33528 KB Output is correct
45 Correct 148 ms 33372 KB Output is correct
46 Correct 187 ms 34592 KB Output is correct
47 Correct 123 ms 29840 KB Output is correct
48 Correct 108 ms 32248 KB Output is correct
49 Correct 141 ms 32856 KB Output is correct
50 Correct 146 ms 31080 KB Output is correct
51 Correct 130 ms 29876 KB Output is correct
52 Correct 150 ms 30684 KB Output is correct
53 Correct 125 ms 31376 KB Output is correct
54 Correct 114 ms 30732 KB Output is correct
55 Correct 144 ms 30736 KB Output is correct
56 Correct 161 ms 32428 KB Output is correct
57 Correct 150 ms 31324 KB Output is correct
58 Correct 168 ms 33196 KB Output is correct
59 Correct 137 ms 31156 KB Output is correct
60 Correct 156 ms 31704 KB Output is correct
61 Correct 139 ms 32180 KB Output is correct
62 Correct 27 ms 24020 KB Output is correct
63 Correct 26 ms 24312 KB Output is correct
64 Correct 124 ms 28936 KB Output is correct
65 Correct 146 ms 25668 KB Output is correct
66 Correct 123 ms 25452 KB Output is correct
67 Execution timed out 1080 ms 49560 KB Time limit exceeded
68 Halted 0 ms 0 KB -