oj.uz

Submission #678863

# Submission time Handle Problem Language Result Execution time Memory
678863 2023-01-06T18:46:26 Z rainboy Fences (JOI18_fences) C++17
100 / 100
 14 ms 628 KB 
#include <math.h>
#include <stdio.h>

#define N	104
#define INF	1e9
#define eps	1e-9

double abs_(double a) { return a > 0 ? a : -a; }
double min(double a, double b) { return a < b ? a : b; }
double max(double a, double b) { return a > b ? a : b; }

double cross2(double x1, double y1, double x2, double y2) {
	return x1 * y2 - x2 * y1;
}

double cross(double x0, double y0, double x1, double y1, double x2, double y2) {
	return cross2(x1 - x0, y1 - y0, x2 - x0, y2 - y0);
}

double dot2(double x1, double y1, double x2, double y2) {
	return x1 * x2 + y1 * y2;
}

double dot(double x0, double y0, double x1, double y1, double x2, double y2) {
	return dot2(x1 - x0, y1 - y0, x2 - x0, y2 - y0);
}

int intersect(double x1, double y1, double x2, double y2, double x3, double y3, double x4, double y4) {
	double a, b;

	if (abs_(cross2(x2 - x1, y2 - y1, x4 - x3, y4 - y3)) < eps)
		return 0;
	a = cross(x1, y1, x3, y3, x4, y4) * cross(x2, y2, x3, y3, x4, y4);
	b = cross(x3, y3, x1, y1, x2, y2) * cross(x4, y4, x1, y1, x2, y2);
	return a < eps && b < -eps || a < -eps && b < eps;
}

int hit(double x1, double y1, double x2, double y2) {
	double tmp;

	if (y1 < y2)
		tmp = x1, x1 = x2, x2 = tmp, tmp = y1, y1 = y2, y2 = tmp;
	return y1 > 0 && y2 <= 0 && cross2(x1, y1, x2, y2) < 0;
}

int xx[N * 2], yy[N * 2], n, s; double dd[N * 2][N * 2];

void add(int i, int j, int x0, int y0, int x1, int y1, int x2, int y2) {
	double t, x3, y3, d;
	int i0, j0, i1, j1, c;

	t = min(max(dot(x1, y1, x0, y0, x2, y2) / dot(x1, y1, x2, y2, x2, y2), 0), 1);
	x3 = x1 + (x2 - x1) * t, y3 = y1 + (y2 - y1) * t;
	if (intersect(x0, y0, x3, y3, -s, -s, -s, s))
		return;
	if (intersect(x0, y0, x3, y3, -s, s, s, s))
		return;
	if (intersect(x0, y0, x3, y3, s, s, s, -s))
		return;
	if (intersect(x0, y0, x3, y3, s, -s, -s, -s))
		return;
	if (abs_((x0 + x3) / 2) <= s - eps && abs_((y0 + y3) / 2) <= s - eps)
		return;
	i0 = i << 1, i1 = i0 | 1, j0 = j << 1, j1 = j0 | 1;
	d = hypot(x3 - x0, y3 - y0);
	c = hit(xx[i0], yy[i0], x0, y0) ^ hit(x0, y0, x3, y3) ^ hit(x3, y3, xx[j0], yy[j0]);
	if (c == 0) {
		dd[i0][j0] = min(dd[i0][j0], d), dd[j0][i0] = min(dd[j0][i0], d);
		dd[i1][j1] = min(dd[i1][j1], d), dd[j1][i1] = min(dd[j1][i1], d);
	} else {
		dd[i0][j1] = min(dd[i0][j1], d), dd[j1][i0] = min(dd[j1][i0], d);
		dd[i1][j0] = min(dd[i1][j0], d), dd[j0][i1] = min(dd[j0][i1], d);
	}
}

int main() {
	int i, j, k;
	double ans;

	scanf("%d%d", &n, &s), n += 4;
	xx[0] = -s, yy[0] = -s, xx[1] = -s, yy[1] = -s;
	xx[2] = -s, yy[2] = s, xx[3] = -s, yy[3] = s;
	xx[4] = s, yy[4] = -s, xx[5] = s, yy[5] = -s;
	xx[6] = s, yy[6] = s, xx[7] = s, yy[7] = s;
	for (i = 8; i < n * 2; i++)
		scanf("%d%d", &xx[i], &yy[i]);
	for (i = 0; i < n * 2; i++)
		for (j = 0; j < n * 2; j++)
			dd[i][j] = i == j ? 0 : INF;
	for (i = 0; i < n; i++)
		for (j = 0; j < n; j++)
			if (i != j) {
				add(i, j, xx[i << 1 | 0], yy[i << 1 | 0], xx[j << 1 | 0], yy[j << 1 | 0], xx[j << 1 | 1], yy[j << 1 | 1]);
				add(i, j, xx[i << 1 | 1], yy[i << 1 | 1], xx[j << 1 | 0], yy[j << 1 | 0], xx[j << 1 | 1], yy[j << 1 | 1]);
			}
	for (k = 0; k < n * 2; k++)
		for (i = 0; i < n * 2; i++)
			for (j = 0; j < n * 2; j++)
				dd[i][j] = min(dd[i][j], dd[i][k] + dd[k][j]);
	ans = INF;
	for (i = 0; i < n; i++)
		ans = min(ans, dd[i << 1 | 0][i << 1 | 1]);
	printf("%.10f\n", ans);
	return 0;
}

Compilation message

fences.cpp: In function 'int intersect(double, double, double, double, double, double, double, double)':
fences.cpp:35:17: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   35 |  return a < eps && b < -eps || a < -eps && b < eps;
      |                 ^
fences.cpp: In function 'int main()':
fences.cpp:80:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   80 |  scanf("%d%d", &n, &s), n += 4;
      |  ~~~~~^~~~~~~~~~~~~~~~
fences.cpp:86:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   86 |   scanf("%d%d", &xx[i], &yy[i]);
      |   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 288 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 1 ms 256 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 0 ms 284 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 0 ms 288 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 212 KB Output is correct
16 Correct 0 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 0 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 0 ms 212 KB Output is correct

Subtask #2
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 288 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 1 ms 256 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 0 ms 284 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 0 ms 288 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 212 KB Output is correct
16 Correct 0 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 0 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 0 ms 212 KB Output is correct
21 Correct 0 ms 212 KB Output is correct
22 Correct 0 ms 288 KB Output is correct
23 Correct 1 ms 284 KB Output is correct
24 Correct 1 ms 292 KB Output is correct
25 Correct 0 ms 212 KB Output is correct
26 Correct 1 ms 212 KB Output is correct
27 Correct 1 ms 212 KB Output is correct
28 Correct 0 ms 212 KB Output is correct
29 Correct 0 ms 212 KB Output is correct
30 Correct 0 ms 212 KB Output is correct
31 Correct 0 ms 212 KB Output is correct
32 Correct 0 ms 212 KB Output is correct
33 Correct 0 ms 288 KB Output is correct
34 Correct 1 ms 212 KB Output is correct
35 Correct 1 ms 212 KB Output is correct
36 Correct 0 ms 212 KB Output is correct
37 Correct 1 ms 212 KB Output is correct
38 Correct 0 ms 212 KB Output is correct
39 Correct 0 ms 212 KB Output is correct
40 Correct 0 ms 212 KB Output is correct
41 Correct 1 ms 212 KB Output is correct
42 Correct 0 ms 212 KB Output is correct
43 Correct 1 ms 212 KB Output is correct

Subtask #3
49.0 / 49.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 288 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 1 ms 256 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 0 ms 284 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 0 ms 288 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 212 KB Output is correct
16 Correct 0 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 0 ms 212 KB Output is correct
19 Correct 0 ms 212 KB Output is correct
20 Correct 0 ms 212 KB Output is correct
21 Correct 0 ms 212 KB Output is correct
22 Correct 0 ms 288 KB Output is correct
23 Correct 1 ms 284 KB Output is correct
24 Correct 1 ms 292 KB Output is correct
25 Correct 0 ms 212 KB Output is correct
26 Correct 1 ms 212 KB Output is correct
27 Correct 1 ms 212 KB Output is correct
28 Correct 0 ms 212 KB Output is correct
29 Correct 0 ms 212 KB Output is correct
30 Correct 0 ms 212 KB Output is correct
31 Correct 0 ms 212 KB Output is correct
32 Correct 0 ms 212 KB Output is correct
33 Correct 0 ms 288 KB Output is correct
34 Correct 1 ms 212 KB Output is correct
35 Correct 1 ms 212 KB Output is correct
36 Correct 0 ms 212 KB Output is correct
37 Correct 1 ms 212 KB Output is correct
38 Correct 0 ms 212 KB Output is correct
39 Correct 0 ms 212 KB Output is correct
40 Correct 0 ms 212 KB Output is correct
41 Correct 1 ms 212 KB Output is correct
42 Correct 0 ms 212 KB Output is correct
43 Correct 1 ms 212 KB Output is correct
44 Correct 11 ms 620 KB Output is correct
45 Correct 9 ms 624 KB Output is correct
46 Correct 9 ms 624 KB Output is correct
47 Correct 9 ms 596 KB Output is correct
48 Correct 10 ms 628 KB Output is correct
49 Correct 9 ms 596 KB Output is correct
50 Correct 10 ms 596 KB Output is correct
51 Correct 10 ms 596 KB Output is correct
52 Correct 14 ms 624 KB Output is correct
53 Correct 10 ms 548 KB Output is correct
54 Correct 10 ms 624 KB Output is correct
55 Correct 9 ms 596 KB Output is correct
56 Correct 9 ms 540 KB Output is correct
57 Correct 9 ms 596 KB Output is correct
58 Correct 9 ms 620 KB Output is correct
59 Correct 9 ms 596 KB Output is correct
60 Correct 9 ms 596 KB Output is correct
61 Correct 10 ms 596 KB Output is correct
62 Correct 1 ms 340 KB Output is correct
63 Correct 0 ms 340 KB Output is correct
64 Correct 8 ms 620 KB Output is correct
65 Correct 9 ms 628 KB Output is correct
66 Correct 8 ms 596 KB Output is correct
67 Correct 8 ms 596 KB Output is correct
68 Correct 8 ms 520 KB Output is correct
69 Correct 9 ms 596 KB Output is correct
70 Correct 8 ms 608 KB Output is correct
71 Correct 9 ms 624 KB Output is correct
72 Correct 9 ms 596 KB Output is correct