oj.uz

Submission #529463

# Submission time Handle Problem Language Result Execution time Memory
529463 2022-02-23T03:43:42 Z 8e7 Fences (JOI18_fences) C++17
100 / 100
 59 ms 1720 KB 
//Challenge: Accepted
#include <bits/stdc++.h>
using namespace std;
#ifdef zisk
void debug(){cout << endl;}
template<class T, class ... U> void debug(T a, U ...b ){cout << a << " ", debug(b...);}
template<class T> void pary(T l, T r) {
	while (l != r) cout << *l << " ", l++;
	cout << endl;
}
#else
#define debug(...) 0
#define pary(...) 0
#endif
#define ll long long
#define maxn 420
#define pii pair<double, double>
#define eps 1e-9
#define x first
#define y second
#define io ios_base::sync_with_stdio(0);cin.tie(0);

pii vec(pii p, pii q) {return {q.x - p.x, q.y - p.y};}
pii operator *(pii p, double x) {return {p.x * x, p.y * x};}
pii operator +(pii p, pii q){return {p.x + q.x, p.y + q.y};}
double dot(pii p, pii q){return p.x * q.x + p.y * q.y;}
double cross(pii p, pii q){return p.x * q.y - p.y * q.x;}
int sgn(double x){return (x > eps ? 1 : (x > -eps ? 0 : -1));}
bool inl(pii p, pii l1, pii l2) {
	return abs(cross(vec(p, l1), vec(p, l2))) <= eps && dot(vec(p, l1), vec(p, l2)) <= eps;
}
bool inter(pii p1, pii p2, pii q1, pii q2) {
	if (inl(p1, q1, q2) || inl(p2, q1, q2) || inl(q1, p1, p2) || inl(q2, p1, p2)) return 1;
	if (sgn(cross(vec(p1, q1), vec(p1, q2))) != sgn(cross(vec(p2, q1), vec(p2, q2))) &&
sgn(cross(vec(q1, p1), vec(q1, p2))) != sgn(cross(vec(q2, p1), vec(q2, p2)))) return 1;
	return 0;
}
double sd(pii p, pii q){return (q.x - p.x) * (q.x - p.x) + (q.y - p.y) * (q.y - p.y);}

pii getpnt(pii p, pii l1, pii l2) {
	pii vi = vec(l1, l2);
	if (sgn(dot(vi, vec(l1, p))) * sgn(dot(vi, vec(l2, p))) != 1) {
		double len = dot(vec(l1, p), vi) / sd(l1, l2);
		return l1 + (vi*len);
	} else {
		if (sd(p, l1) < sd(p, l2)) return l1;
		else return l2;
	}
}
double dis(pii p, pii l1, pii l2) {
	return sqrt(sd(p, getpnt(p, l1, l2)));	
}

pii edge[4];
bool valid(pii p, pii q) {
	bool op[4], oq[4];
	int pc = 0, qc = 0;
	for (int i = 0;i < 4;i++) {
		op[i] = inl(p, edge[i], edge[(i+1)%4]);
		oq[i] = inl(q, edge[i], edge[(i+1)%4]);
		pc += op[i] ? 1 : 0, qc += oq[i] ? 1 : 0;
	}

	if (pc && qc) {
		for (int i = 0;i < 4;i++) {
			if (op[i] && oq[i]) return 1;
		}
		return 0;
	} else {
		for (int i = 0;i < 4;i++) {
			if (inter(p, q, edge[i], edge[(i+1)%4])) {
				if (!op[i] && !oq[i]) return 0;
			}
		}
		return 1;
	}	
}

const pii ray0 = {0, 0}, ray1 = {maxn, 1};
pii a[maxn];

const double inf = 1e9;
double g[maxn][maxn];
int main() {
	io
	int n, s;
	cin >> n >> s;
	for (int i = 0;i < n;i++) {
		cin >> a[2*i].x >> a[2*i].y >> a[2*i+1].x >> a[2*i+1].y;
	}	
	edge[0] = {s, s}, edge[1] = {s, -s}, edge[2] = {-s, -s}, edge[3] = {-s, s};

	/*	
	pii test;
	cin >> test.x >> test.y;
	cout << dis(test, a[4], a[5]) << endl;
	*/
	
	int m = 4 * n + 8;
	for (int i = 0;i < m;i++) {
		for (int j = 0;j < m;j++) g[i][j] = inf;
		g[i][i] = 0;
	}

	
	double ans = 8 * s;
	auto chmin = [&](double &x, double d){x = min(x, d);};
	auto addedge = [&](int i, int j, double d, bool type) {
		if (type) {
			chmin(g[i*2][j*2+1], d);
			chmin(g[j*2+1][i*2], d);
			chmin(g[i*2+1][j*2], d);
			chmin(g[j*2][i*2+1], d);
		} else {
			chmin(g[i*2][j*2], d);
			chmin(g[j*2][i*2], d);
			chmin(g[i*2+1][j*2+1], d);
			chmin(g[j*2+1][i*2+1], d);
		}
	};
	auto change = [&](pii p, pii q) {return inter(p, q, ray0, ray1);};
	for (int i = 0;i < 2 * n;i++) {
		for (int j = 0;j < 2 * n;j++) {
			if (i == j) continue;
			if (i % 2 == 0 && j == i+1) {
				addedge(i, j, 0, change(a[i], a[j]));	
			} else {
				pii best;
				if (j % 2) best = getpnt(a[i], a[j], a[j-1]);
				else best = getpnt(a[i], a[j], a[j+1]);
				if (valid(a[i], best)) {
					addedge(i, j, sqrt(sd(best, a[i])), change(a[i], best) ^ change(best, a[j]));
				}
			}
		}
		if (i % 2 == 0) {
			for (int j = 0;j < 4;j++) {
				pii best = getpnt(edge[j], a[i], a[i+1]);		
				if (valid(edge[j], best)) {
					addedge(2*n+j, i, sqrt(sd(edge[j], best)), change(edge[j], best) ^ change(best, a[i]));
				}
			}	
		}
	}	
	for (int i = 0;i < 4;i++) {
		addedge(2*n+i, 2*n+(i+1)%4, 2*s, change(edge[i], edge[(i+1)%4]));
	}
	for (int k = 0;k < m;k++) {
		for (int i = 0;i < m;i++) {
			for (int j = 0;j < m;j++) {
				g[i][j] = min(g[i][j], g[i][k] + g[k][j]);
			}
		}
	}	
	for (int i = 0;i < m;i+=2) {
		ans = min(ans, g[i][i+1]);
		debug(i, g[i][i+1]);
	}
	/*
	int qu, qv;
	while (cin >> qu >> qv) {
		debug("same: ", g[qu*2][qv*2]);
		debug("dif: ", g[qu*2][qv*2+1]);
	}
	*/
	cout << fixed << setprecision(10) << ans << endl;
}

Compilation message

fences.cpp: In function 'int main()':
fences.cpp:12:20: warning: statement has no effect [-Wunused-value]
   12 | #define debug(...) 0
      |                    ^
fences.cpp:157:3: note: in expansion of macro 'debug'
  157 |   debug(i, g[i][i+1]);
      |   ^~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 0 ms 332 KB Output is correct
4 Correct 0 ms 332 KB Output is correct
5 Correct 0 ms 332 KB Output is correct
6 Correct 0 ms 332 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 0 ms 332 KB Output is correct
10 Correct 0 ms 332 KB Output is correct
11 Correct 0 ms 332 KB Output is correct
12 Correct 0 ms 332 KB Output is correct
13 Correct 0 ms 332 KB Output is correct
14 Correct 0 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 1 ms 332 KB Output is correct
17 Correct 0 ms 332 KB Output is correct
18 Correct 0 ms 332 KB Output is correct
19 Correct 0 ms 332 KB Output is correct
20 Correct 0 ms 332 KB Output is correct

Subtask #2
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 0 ms 332 KB Output is correct
4 Correct 0 ms 332 KB Output is correct
5 Correct 0 ms 332 KB Output is correct
6 Correct 0 ms 332 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 0 ms 332 KB Output is correct
10 Correct 0 ms 332 KB Output is correct
11 Correct 0 ms 332 KB Output is correct
12 Correct 0 ms 332 KB Output is correct
13 Correct 0 ms 332 KB Output is correct
14 Correct 0 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 1 ms 332 KB Output is correct
17 Correct 0 ms 332 KB Output is correct
18 Correct 0 ms 332 KB Output is correct
19 Correct 0 ms 332 KB Output is correct
20 Correct 0 ms 332 KB Output is correct
21 Correct 0 ms 332 KB Output is correct
22 Correct 1 ms 332 KB Output is correct
23 Correct 1 ms 332 KB Output is correct
24 Correct 1 ms 332 KB Output is correct
25 Correct 1 ms 332 KB Output is correct
26 Correct 1 ms 332 KB Output is correct
27 Correct 1 ms 332 KB Output is correct
28 Correct 1 ms 332 KB Output is correct
29 Correct 1 ms 332 KB Output is correct
30 Correct 0 ms 332 KB Output is correct
31 Correct 1 ms 332 KB Output is correct
32 Correct 1 ms 332 KB Output is correct
33 Correct 1 ms 320 KB Output is correct
34 Correct 1 ms 332 KB Output is correct
35 Correct 1 ms 332 KB Output is correct
36 Correct 1 ms 332 KB Output is correct
37 Correct 1 ms 332 KB Output is correct
38 Correct 0 ms 332 KB Output is correct
39 Correct 1 ms 316 KB Output is correct
40 Correct 1 ms 332 KB Output is correct
41 Correct 1 ms 332 KB Output is correct
42 Correct 0 ms 332 KB Output is correct
43 Correct 0 ms 332 KB Output is correct

Subtask #3
49.0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 332 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 0 ms 332 KB Output is correct
4 Correct 0 ms 332 KB Output is correct
5 Correct 0 ms 332 KB Output is correct
6 Correct 0 ms 332 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 0 ms 332 KB Output is correct
10 Correct 0 ms 332 KB Output is correct
11 Correct 0 ms 332 KB Output is correct
12 Correct 0 ms 332 KB Output is correct
13 Correct 0 ms 332 KB Output is correct
14 Correct 0 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 1 ms 332 KB Output is correct
17 Correct 0 ms 332 KB Output is correct
18 Correct 0 ms 332 KB Output is correct
19 Correct 0 ms 332 KB Output is correct
20 Correct 0 ms 332 KB Output is correct
21 Correct 0 ms 332 KB Output is correct
22 Correct 1 ms 332 KB Output is correct
23 Correct 1 ms 332 KB Output is correct
24 Correct 1 ms 332 KB Output is correct
25 Correct 1 ms 332 KB Output is correct
26 Correct 1 ms 332 KB Output is correct
27 Correct 1 ms 332 KB Output is correct
28 Correct 1 ms 332 KB Output is correct
29 Correct 1 ms 332 KB Output is correct
30 Correct 0 ms 332 KB Output is correct
31 Correct 1 ms 332 KB Output is correct
32 Correct 1 ms 332 KB Output is correct
33 Correct 1 ms 320 KB Output is correct
34 Correct 1 ms 332 KB Output is correct
35 Correct 1 ms 332 KB Output is correct
36 Correct 1 ms 332 KB Output is correct
37 Correct 1 ms 332 KB Output is correct
38 Correct 0 ms 332 KB Output is correct
39 Correct 1 ms 316 KB Output is correct
40 Correct 1 ms 332 KB Output is correct
41 Correct 1 ms 332 KB Output is correct
42 Correct 0 ms 332 KB Output is correct
43 Correct 0 ms 332 KB Output is correct
44 Correct 59 ms 1612 KB Output is correct
45 Correct 52 ms 1612 KB Output is correct
46 Correct 50 ms 1648 KB Output is correct
47 Correct 50 ms 1612 KB Output is correct
48 Correct 52 ms 1612 KB Output is correct
49 Correct 51 ms 1612 KB Output is correct
50 Correct 50 ms 1660 KB Output is correct
51 Correct 58 ms 1656 KB Output is correct
52 Correct 50 ms 1612 KB Output is correct
53 Correct 50 ms 1648 KB Output is correct
54 Correct 51 ms 1612 KB Output is correct
55 Correct 52 ms 1612 KB Output is correct
56 Correct 52 ms 1644 KB Output is correct
57 Correct 51 ms 1612 KB Output is correct
58 Correct 53 ms 1660 KB Output is correct
59 Correct 59 ms 1612 KB Output is correct
60 Correct 51 ms 1612 KB Output is correct
61 Correct 50 ms 1612 KB Output is correct
62 Correct 1 ms 460 KB Output is correct
63 Correct 1 ms 460 KB Output is correct
64 Correct 46 ms 1608 KB Output is correct
65 Correct 51 ms 1648 KB Output is correct
66 Correct 45 ms 1612 KB Output is correct
67 Correct 46 ms 1612 KB Output is correct
68 Correct 47 ms 1604 KB Output is correct
69 Correct 53 ms 1720 KB Output is correct
70 Correct 42 ms 1484 KB Output is correct
71 Correct 48 ms 1604 KB Output is correct
72 Correct 53 ms 1648 KB Output is correct