oj.uz

Submission #132160

# Submission time Handle Problem Language Result Execution time Memory
132160 2019-07-18T11:13:54 Z onjo0127 Fences (JOI18_fences) C++11
100 / 100
 136 ms 26816 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; };
struct edg { int X; double Y; bool IT; };
 
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<edg> 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(it.IT) 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, bool it) {
	// printf("u: %d, v: %d, (%f, %f) -- (%f, %f), cost: %f, cross: %d\n", u, v, T[u].D.X, T[u].D.Y, T[v].D.X, T[v].D.Y, c, it);
	adj[u].push_back({v, c, it});
	adj[v].push_back({u, c, it});
}
 
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});
 
	K = T.size();
 
	for(int i=1; i<=N; i++) {
		make_edge(2*i-2, 2*i-1, 0, its(A[i], I));
		for(int j=0; j<K; j++) {
			if(i == T[j].id) continue;
			pdd pu = push(A[i], T[j].D);
			double dp = dst(pu, T[j].D), ds = dst(T[j].D, A[i].S), de = dst(T[j].D, A[i].E);
			if(!ok({T[j].D, pu}) || !on(A[i], pu)) dp = 1e9;
			if(!ok({T[j].D, A[i].S})) ds = 1e9;
			if(!ok({T[j].D, A[i].E})) de = 1e9;
			if(dp < 1e8) {
				make_edge(j, 2*i-2, dp, its({pu, T[j].D}, I) ^ its({pu, A[i].S}, I));
				make_edge(j, 2*i-1, dp, its({pu, T[j].D}, I) ^ its({pu, A[i].E}, I));
			}
			if(ds < 1e8) make_edge(j, 2*i-2, ds, its({A[i].S, T[j].D}, I));
			if(de < 1e8) make_edge(j, 2*i-1, de, its({A[i].E, T[j].D}, I));
		}
	}
 
	for(int i=2*N; i<2*N+4; i++) {
		for(int j=i+1; j<2*N+4; j++) {
			if(!ok({T[i].D, T[j].D})) continue;
			make_edge(i, j, dst(T[i].D, T[j].D), its({T[i].D, T[j].D}, I));
		}
	}
 
	// 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<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: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:28:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 24 ms 23800 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 29 ms 23800 KB Output is correct
6 Correct 25 ms 23800 KB Output is correct
7 Correct 30 ms 23896 KB Output is correct
8 Correct 30 ms 23800 KB Output is correct
9 Correct 25 ms 23800 KB Output is correct
10 Correct 26 ms 23800 KB Output is correct
11 Correct 25 ms 23800 KB Output is correct
12 Correct 25 ms 23800 KB Output is correct
13 Correct 25 ms 23772 KB Output is correct
14 Correct 25 ms 23800 KB Output is correct
15 Correct 25 ms 23800 KB Output is correct
16 Correct 25 ms 23800 KB Output is correct
17 Correct 25 ms 23800 KB Output is correct
18 Correct 25 ms 23772 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 24 ms 23800 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 29 ms 23800 KB Output is correct
6 Correct 25 ms 23800 KB Output is correct
7 Correct 30 ms 23896 KB Output is correct
8 Correct 30 ms 23800 KB Output is correct
9 Correct 25 ms 23800 KB Output is correct
10 Correct 26 ms 23800 KB Output is correct
11 Correct 25 ms 23800 KB Output is correct
12 Correct 25 ms 23800 KB Output is correct
13 Correct 25 ms 23772 KB Output is correct
14 Correct 25 ms 23800 KB Output is correct
15 Correct 25 ms 23800 KB Output is correct
16 Correct 25 ms 23800 KB Output is correct
17 Correct 25 ms 23800 KB Output is correct
18 Correct 25 ms 23772 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 23800 KB Output is correct
24 Correct 25 ms 23804 KB Output is correct
25 Correct 31 ms 23772 KB Output is correct
26 Correct 31 ms 23800 KB Output is correct
27 Correct 26 ms 23800 KB Output is correct
28 Correct 37 ms 23800 KB Output is correct
29 Correct 30 ms 23800 KB Output is correct
30 Correct 26 ms 23800 KB Output is correct
31 Correct 27 ms 23804 KB Output is correct
32 Correct 26 ms 23800 KB Output is correct
33 Correct 26 ms 23800 KB Output is correct
34 Correct 26 ms 23800 KB Output is correct
35 Correct 26 ms 23928 KB Output is correct
36 Correct 26 ms 23800 KB Output is correct
37 Correct 26 ms 23800 KB Output is correct
38 Correct 29 ms 23800 KB Output is correct
39 Correct 28 ms 23800 KB Output is correct
40 Correct 26 ms 23800 KB Output is correct
41 Correct 25 ms 23800 KB Output is correct
42 Correct 25 ms 23800 KB Output is correct
43 Correct 26 ms 23800 KB Output is correct

Subtask #3
49.0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 24 ms 23800 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 29 ms 23800 KB Output is correct
6 Correct 25 ms 23800 KB Output is correct
7 Correct 30 ms 23896 KB Output is correct
8 Correct 30 ms 23800 KB Output is correct
9 Correct 25 ms 23800 KB Output is correct
10 Correct 26 ms 23800 KB Output is correct
11 Correct 25 ms 23800 KB Output is correct
12 Correct 25 ms 23800 KB Output is correct
13 Correct 25 ms 23772 KB Output is correct
14 Correct 25 ms 23800 KB Output is correct
15 Correct 25 ms 23800 KB Output is correct
16 Correct 25 ms 23800 KB Output is correct
17 Correct 25 ms 23800 KB Output is correct
18 Correct 25 ms 23772 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 23800 KB Output is correct
24 Correct 25 ms 23804 KB Output is correct
25 Correct 31 ms 23772 KB Output is correct
26 Correct 31 ms 23800 KB Output is correct
27 Correct 26 ms 23800 KB Output is correct
28 Correct 37 ms 23800 KB Output is correct
29 Correct 30 ms 23800 KB Output is correct
30 Correct 26 ms 23800 KB Output is correct
31 Correct 27 ms 23804 KB Output is correct
32 Correct 26 ms 23800 KB Output is correct
33 Correct 26 ms 23800 KB Output is correct
34 Correct 26 ms 23800 KB Output is correct
35 Correct 26 ms 23928 KB Output is correct
36 Correct 26 ms 23800 KB Output is correct
37 Correct 26 ms 23800 KB Output is correct
38 Correct 29 ms 23800 KB Output is correct
39 Correct 28 ms 23800 KB Output is correct
40 Correct 26 ms 23800 KB Output is correct
41 Correct 25 ms 23800 KB Output is correct
42 Correct 25 ms 23800 KB Output is correct
43 Correct 26 ms 23800 KB Output is correct
44 Correct 54 ms 26744 KB Output is correct
45 Correct 69 ms 26588 KB Output is correct
46 Correct 72 ms 25936 KB Output is correct
47 Correct 77 ms 25424 KB Output is correct
48 Correct 59 ms 26756 KB Output is correct
49 Correct 81 ms 26640 KB Output is correct
50 Correct 81 ms 25824 KB Output is correct
51 Correct 78 ms 25464 KB Output is correct
52 Correct 80 ms 25924 KB Output is correct
53 Correct 67 ms 25592 KB Output is correct
54 Correct 69 ms 25904 KB Output is correct
55 Correct 85 ms 26188 KB Output is correct
56 Correct 77 ms 26060 KB Output is correct
57 Correct 82 ms 25760 KB Output is correct
58 Correct 79 ms 25784 KB Output is correct
59 Correct 77 ms 25860 KB Output is correct
60 Correct 83 ms 26076 KB Output is correct
61 Correct 76 ms 26348 KB Output is correct
62 Correct 26 ms 23800 KB Output is correct
63 Correct 26 ms 23928 KB Output is correct
64 Correct 107 ms 26816 KB Output is correct
65 Correct 136 ms 25504 KB Output is correct
66 Correct 117 ms 25296 KB Output is correct
67 Correct 80 ms 26640 KB Output is correct
68 Correct 77 ms 26664 KB Output is correct
69 Correct 102 ms 26488 KB Output is correct
70 Correct 98 ms 26092 KB Output is correct
71 Correct 112 ms 26504 KB Output is correct
72 Correct 89 ms 25720 KB Output is correct