oj.uz

Submission #57062

# Submission time Handle Problem Language Result Execution time Memory
57062 2018-07-13T17:43:06 Z cki86201 Fences (JOI18_fences) C++11
51 / 100
 1000 ms 5360 KB 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>
#include <math.h>
#include <assert.h>
#include <queue>
#include <map>
#include <set>
#include <string>
#include <algorithm>
#include <iostream>
#include <functional>
#include <unordered_map>

using namespace std;
typedef pair<int, int> pii;
typedef long long ll;
#define Fi first
#define Se second
#define pb(x) push_back(x)
#define szz(x) (int)x.size()
#define rep(i, n) for(int i=0;i<n;i++)
#define all(x) x.begin(), x.end()
typedef tuple<int, int, int> t3;

struct point {
	double x, y;
	point(){}
	point(double x, double y) : x(x), y(y) {}
	point operator-(point a) { return point(x - a.x, y - a.y); }
	point operator+(point a) { return point(x + a.x, y + a.y); }
	double operator*(point a) { return x * a.x + y * a.y; }
	point operator*(double a) { return point(x * a, y * a); }
	double operator/(point a) { return x * a.y - y * a.x; }
	double length() { return hypot(x, y); }
};

vector <point> V;
int N, S;
point In[110][2];
const double EPS = 1e-9;

inline int p1_in(double x) { return -S + EPS < x && x < S - EPS; }
inline int seg1_in(double l1, double r1, double l2, double r2) {
	if(l1 > r1) swap(l1, r1);
	if(l2 > r2) swap(l2, r2);
	return max(l1, l2) + EPS < min(r1, r2);
}

int is_in(point a, point b) {
	if(fabs(a.x - b.x) <= EPS) { swap(a.x, a.y); swap(b.x, b.y); }
	if(fabs(a.x - b.x) <= EPS) {
		return p1_in(a.x) && p1_in(a.y);
	}
	if(fabs(a.y - b.y) <= EPS) {
		if(p1_in(a.y) && seg1_in(a.x, b.x, -S, S)) return 1;
		return 0;
	}
	double lx = (-S - a.x) / (b.x - a.x);
	double rx = (S - a.x) / (b.x - a.x);
	if(lx > rx) swap(lx, rx);
	double ly = (-S - a.y) / (b.y - a.y);
	double ry = (S - a.y) / (b.y - a.y);
	if(ly > ry) swap(ly, ry);
	double L = max({lx, ly, 0.0});
	double R = min({rx, ry, 1.0});
	if(L + EPS < R) return 1;
	return 0;
}

typedef pair<double, int> pdi;

vector <point> PS;
vector <pdi> E[50050];

int sign(double x) {
	if(fabs(x) <= EPS) return 0;
	return x > 0 ? 1 : -1;
}

int seg2_in(point a, point b, point c, point d) {
	return sign((b-a) / (c-a)) * sign((b-a) / (d-a)) == -1 && sign((d-c) / (a-c)) * sign((d-c) / (b-c)) == -1;
}

int meet(int a, int b) {
	point p1 = point(0, 0);
	point p2 = point(400 + sqrt(2), 1);
	return seg2_in(PS[a], PS[b], p1, p2);
}

void add_edge(int a, int b, double len = -1) {
	if(is_in(PS[a], PS[b])) return;
	int c = meet(a, b);
	if(len == -1) len = (PS[a] - PS[b]).length();
	rep(u, 2) {
		E[a<<1^u].pb(pdi(len, b<<1^u^c));
		E[b<<1^u^c].pb(pdi(len, a<<1^u));
	}
}

double dis[50050];
double get_min(int x) {
	int s = x * 2, des = s + 1;
	priority_queue <pdi, vector<pdi>, greater<pdi> > pq;
	int N = szz(PS) * 2;
	rep(i, N) dis[i] = 1e9;
	dis[s] = 0; pq.push(pdi(0, s));
	while(!pq.empty()) {
		pdi t = pq.top(); pq.pop();
		if(dis[t.Se] != t.Fi) continue;
		if(t.Se == des) return t.Fi;
		for(pdi e : E[t.Se]) {
			if(e.Fi + t.Fi < dis[e.Se]) {
				dis[e.Se] = e.Fi + t.Fi;
				pq.push(pdi(dis[e.Se], e.Se));
			}
		}
	}
	return dis[des];
}

void solve(){
	scanf("%d%d", &N, &S);
	for(int x : {-S, S}) for(int y : {-S, S}) PS.pb(point(x, y));
	rep(i, N) {
		int l = szz(PS);
		rep(j, 2) {
			int x, y; scanf("%d%d", &x, &y);
			In[i][j] = point(x, y);
			PS.pb(In[i][j]);
		}
		add_edge(l, l+1, 0);
	}
	rep(i, szz(PS)) rep(j, i) add_edge(i, j);
	rep(i, 2*N+4) rep(j, N) {
		point a = In[j][0], b = In[j][1];
		point p = PS[i];
		if((p-a) * (b-a) > EPS && (p-b) * (a-b) > EPS) {
			double v = ((p-a) * (b-a)) / ((b-a) * (b-a));
			point h = a + (b-a) * v;
			int ok = 1;
			rep(k, N) if(seg2_in(p, h, a, b)) { ok = 0; break; }
		//	printf("p = (%.1f, %.1f), a = (%.1f, %.1f), b = (%.1f, %.1f), h = (%.1f, %.1f)\n", p.x, p.y, a.x, a.y, b.x, b.y, h.x, h.y);
			if(ok) {
				int z = szz(PS);
				PS.pb(h);
				add_edge(2 * j + 4, z, 0);
				add_edge(2 * j + 5, z, 0);
				add_edge(z, i);
			}
		}
	}
	
	double ans = 1e9;
	rep(i, 2*N+4) ans = min(ans, get_min(i));
	printf("%.12f\n", ans);
}

int main(){
	int Tc = 1; //scanf("%d", &Tc);
	for(int tc=1;tc<=Tc;tc++){
		solve();
	}
	return 0;
}

Compilation message

fences.cpp: In function 'void solve()':
fences.cpp:124:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &N, &S);
  ~~~~~^~~~~~~~~~~~~~~~
fences.cpp:129:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    int x, y; scanf("%d%d", &x, &y);
              ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 1528 KB Output is correct
2 Correct 3 ms 1640 KB Output is correct
3 Correct 5 ms 1640 KB Output is correct
4 Correct 4 ms 1640 KB Output is correct
5 Correct 4 ms 1640 KB Output is correct
6 Correct 4 ms 1672 KB Output is correct
7 Correct 5 ms 1744 KB Output is correct
8 Correct 3 ms 1744 KB Output is correct
9 Correct 3 ms 1872 KB Output is correct
10 Correct 3 ms 1872 KB Output is correct
11 Correct 3 ms 1872 KB Output is correct
12 Correct 3 ms 1872 KB Output is correct
13 Correct 3 ms 1872 KB Output is correct
14 Correct 3 ms 1872 KB Output is correct
15 Correct 3 ms 1872 KB Output is correct
16 Correct 3 ms 1872 KB Output is correct
17 Correct 3 ms 1872 KB Output is correct
18 Correct 3 ms 1872 KB Output is correct
19 Correct 3 ms 1872 KB Output is correct
20 Correct 3 ms 1872 KB Output is correct

Subtask #2
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 1528 KB Output is correct
2 Correct 3 ms 1640 KB Output is correct
3 Correct 5 ms 1640 KB Output is correct
4 Correct 4 ms 1640 KB Output is correct
5 Correct 4 ms 1640 KB Output is correct
6 Correct 4 ms 1672 KB Output is correct
7 Correct 5 ms 1744 KB Output is correct
8 Correct 3 ms 1744 KB Output is correct
9 Correct 3 ms 1872 KB Output is correct
10 Correct 3 ms 1872 KB Output is correct
11 Correct 3 ms 1872 KB Output is correct
12 Correct 3 ms 1872 KB Output is correct
13 Correct 3 ms 1872 KB Output is correct
14 Correct 3 ms 1872 KB Output is correct
15 Correct 3 ms 1872 KB Output is correct
16 Correct 3 ms 1872 KB Output is correct
17 Correct 3 ms 1872 KB Output is correct
18 Correct 3 ms 1872 KB Output is correct
19 Correct 3 ms 1872 KB Output is correct
20 Correct 3 ms 1872 KB Output is correct
21 Correct 3 ms 1872 KB Output is correct
22 Correct 3 ms 1872 KB Output is correct
23 Correct 4 ms 1872 KB Output is correct
24 Correct 4 ms 1872 KB Output is correct
25 Correct 3 ms 1872 KB Output is correct
26 Correct 3 ms 1872 KB Output is correct
27 Correct 3 ms 1872 KB Output is correct
28 Correct 4 ms 1872 KB Output is correct
29 Correct 4 ms 1872 KB Output is correct
30 Correct 3 ms 1872 KB Output is correct
31 Correct 4 ms 1872 KB Output is correct
32 Correct 3 ms 1872 KB Output is correct
33 Correct 3 ms 1872 KB Output is correct
34 Correct 3 ms 1872 KB Output is correct
35 Correct 3 ms 1872 KB Output is correct
36 Correct 3 ms 1872 KB Output is correct
37 Correct 3 ms 1872 KB Output is correct
38 Correct 3 ms 1872 KB Output is correct
39 Correct 3 ms 1872 KB Output is correct
40 Correct 3 ms 1872 KB Output is correct
41 Correct 3 ms 1872 KB Output is correct
42 Correct 3 ms 1872 KB Output is correct
43 Correct 3 ms 1872 KB Output is correct

Subtask #3
0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 1528 KB Output is correct
2 Correct 3 ms 1640 KB Output is correct
3 Correct 5 ms 1640 KB Output is correct
4 Correct 4 ms 1640 KB Output is correct
5 Correct 4 ms 1640 KB Output is correct
6 Correct 4 ms 1672 KB Output is correct
7 Correct 5 ms 1744 KB Output is correct
8 Correct 3 ms 1744 KB Output is correct
9 Correct 3 ms 1872 KB Output is correct
10 Correct 3 ms 1872 KB Output is correct
11 Correct 3 ms 1872 KB Output is correct
12 Correct 3 ms 1872 KB Output is correct
13 Correct 3 ms 1872 KB Output is correct
14 Correct 3 ms 1872 KB Output is correct
15 Correct 3 ms 1872 KB Output is correct
16 Correct 3 ms 1872 KB Output is correct
17 Correct 3 ms 1872 KB Output is correct
18 Correct 3 ms 1872 KB Output is correct
19 Correct 3 ms 1872 KB Output is correct
20 Correct 3 ms 1872 KB Output is correct
21 Correct 3 ms 1872 KB Output is correct
22 Correct 3 ms 1872 KB Output is correct
23 Correct 4 ms 1872 KB Output is correct
24 Correct 4 ms 1872 KB Output is correct
25 Correct 3 ms 1872 KB Output is correct
26 Correct 3 ms 1872 KB Output is correct
27 Correct 3 ms 1872 KB Output is correct
28 Correct 4 ms 1872 KB Output is correct
29 Correct 4 ms 1872 KB Output is correct
30 Correct 3 ms 1872 KB Output is correct
31 Correct 4 ms 1872 KB Output is correct
32 Correct 3 ms 1872 KB Output is correct
33 Correct 3 ms 1872 KB Output is correct
34 Correct 3 ms 1872 KB Output is correct
35 Correct 3 ms 1872 KB Output is correct
36 Correct 3 ms 1872 KB Output is correct
37 Correct 3 ms 1872 KB Output is correct
38 Correct 3 ms 1872 KB Output is correct
39 Correct 3 ms 1872 KB Output is correct
40 Correct 3 ms 1872 KB Output is correct
41 Correct 3 ms 1872 KB Output is correct
42 Correct 3 ms 1872 KB Output is correct
43 Correct 3 ms 1872 KB Output is correct
44 Correct 405 ms 5360 KB Output is correct
45 Correct 372 ms 5360 KB Output is correct
46 Correct 381 ms 5360 KB Output is correct
47 Correct 322 ms 5360 KB Output is correct
48 Correct 473 ms 5360 KB Output is correct
49 Correct 538 ms 5360 KB Output is correct
50 Correct 449 ms 5360 KB Output is correct
51 Correct 358 ms 5360 KB Output is correct
52 Correct 368 ms 5360 KB Output is correct
53 Correct 384 ms 5360 KB Output is correct
54 Correct 835 ms 5360 KB Output is correct
55 Execution timed out 1031 ms 5360 KB Time limit exceeded
56 Halted 0 ms 0 KB -