#include <bits/stdc++.h>
using namespace std;
#define sz(x) (int)x.size()
struct Point {
double x, y;
};
/**
* @returns the intersection of the perpendicular line that
* crosses the midpoint of Points a & b with the highway
*/
double max_point(Point a, Point b) {
return (b.x * b.x + b.y * b.y - a.x * a.x - a.y * a.y) / (2 * b.x - 2 * a.x);
}
/**
* @returns the euclidean distance between Points a & b
*/
double dist(Point a, Point b) {
return sqrt((a.x - b.x) * (a.x - b.x) + (a.y - b.y) * (a.y - b.y));
}
int main() {
int n, l;
cin >> n >> l;
deque<Point> stck;
for (int i = 0; i < n; i++) {
Point cur;
cin >> cur.x >> cur.y;
cur.y = abs(cur.y);
// take the one with the lowest y coord
if (sz(stck) && stck.back().x == cur.x) {
if (cur.y >= stck.back().y) {
continue;
} else if (cur.y < stck.back().y) {
stck.pop_back();
}
}
// find "crosses"
while (sz(stck) > 1 && max_point(stck[sz(stck) - 2], stck.back()) > max_point(stck.back(), cur)) {
stck.pop_back();
}
stck.push_back(cur);
}
// out of bounds
while (sz(stck) > 1 && max_point(stck[0], stck[1]) < 0)
stck.pop_front();
while (sz(stck) > 1 && max_point(stck[sz(stck) - 2], stck.back()) > l)
stck.pop_back();
double ans = 0;
for (int x = 0; x < sz(stck); x++) {
Point left = {(x ? max_point(stck[x], stck[x - 1]) : 0), 0};
Point right = {(x < sz(stck) - 1 ? max_point(stck[x], stck[x + 1]) : l), 0};
if (left.x < 0 || right.x > l || right.x < 0 || left.x > l)
continue;
ans = max({ans, dist(stck[x], left), dist(stck[x], right)});
}
cout << fixed << setprecision(6) << ans << endl;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
1 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
1 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
348 KB |
Output is correct |
2 |
Correct |
2 ms |
488 KB |
Output is correct |
3 |
Correct |
1 ms |
348 KB |
Output is correct |
4 |
Correct |
2 ms |
484 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
344 KB |
Output is correct |
2 |
Correct |
4 ms |
348 KB |
Output is correct |
3 |
Correct |
3 ms |
348 KB |
Output is correct |
4 |
Correct |
4 ms |
500 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
348 KB |
Output is correct |
2 |
Correct |
4 ms |
360 KB |
Output is correct |
3 |
Correct |
3 ms |
612 KB |
Output is correct |
4 |
Correct |
4 ms |
512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
4 ms |
360 KB |
Output is correct |
2 |
Correct |
4 ms |
360 KB |
Output is correct |
3 |
Correct |
3 ms |
356 KB |
Output is correct |
4 |
Correct |
5 ms |
360 KB |
Output is correct |
5 |
Correct |
3 ms |
356 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
48 ms |
1328 KB |
Output is correct |
2 |
Correct |
54 ms |
1308 KB |
Output is correct |
3 |
Correct |
38 ms |
872 KB |
Output is correct |
4 |
Correct |
59 ms |
1552 KB |
Output is correct |
5 |
Correct |
34 ms |
868 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
46 ms |
1108 KB |
Output is correct |
2 |
Correct |
46 ms |
1116 KB |
Output is correct |
3 |
Correct |
63 ms |
1292 KB |
Output is correct |
4 |
Correct |
60 ms |
1616 KB |
Output is correct |
5 |
Correct |
75 ms |
1872 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
48 ms |
2384 KB |
Output is correct |
2 |
Correct |
66 ms |
1548 KB |
Output is correct |
3 |
Correct |
55 ms |
2388 KB |
Output is correct |
4 |
Correct |
85 ms |
2132 KB |
Output is correct |
5 |
Correct |
56 ms |
1180 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
73 ms |
1876 KB |
Output is correct |
2 |
Correct |
82 ms |
1720 KB |
Output is correct |
3 |
Correct |
61 ms |
1616 KB |
Output is correct |
4 |
Correct |
89 ms |
2140 KB |
Output is correct |
5 |
Correct |
70 ms |
1632 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
77 ms |
3192 KB |
Output is correct |
2 |
Correct |
70 ms |
1692 KB |
Output is correct |
3 |
Correct |
60 ms |
1568 KB |
Output is correct |
4 |
Correct |
84 ms |
2384 KB |
Output is correct |
5 |
Correct |
70 ms |
1620 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
296 ms |
12824 KB |
Output is correct |
2 |
Correct |
359 ms |
8088 KB |
Output is correct |
3 |
Correct |
348 ms |
7576 KB |
Output is correct |
4 |
Correct |
417 ms |
9736 KB |
Output is correct |
5 |
Correct |
377 ms |
7308 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
389 ms |
8588 KB |
Output is correct |
2 |
Correct |
368 ms |
7748 KB |
Output is correct |
3 |
Correct |
314 ms |
7504 KB |
Output is correct |
4 |
Correct |
434 ms |
9748 KB |
Output is correct |
5 |
Correct |
390 ms |
7568 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
376 ms |
15280 KB |
Output is correct |
2 |
Correct |
438 ms |
9736 KB |
Output is correct |
3 |
Correct |
413 ms |
8976 KB |
Output is correct |
4 |
Correct |
520 ms |
12380 KB |
Output is correct |
5 |
Correct |
423 ms |
8528 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
447 ms |
10132 KB |
Output is correct |
2 |
Correct |
424 ms |
9088 KB |
Output is correct |
3 |
Correct |
363 ms |
8272 KB |
Output is correct |
4 |
Correct |
511 ms |
11916 KB |
Output is correct |
5 |
Correct |
438 ms |
9296 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
408 ms |
17808 KB |
Output is correct |
2 |
Correct |
506 ms |
11092 KB |
Output is correct |
3 |
Correct |
491 ms |
10320 KB |
Output is correct |
4 |
Correct |
629 ms |
13708 KB |
Output is correct |
5 |
Correct |
485 ms |
9232 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
517 ms |
12164 KB |
Output is correct |
2 |
Correct |
490 ms |
10440 KB |
Output is correct |
3 |
Correct |
449 ms |
10632 KB |
Output is correct |
4 |
Correct |
589 ms |
13592 KB |
Output is correct |
5 |
Correct |
511 ms |
10388 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
465 ms |
20276 KB |
Output is correct |
2 |
Correct |
576 ms |
12708 KB |
Output is correct |
3 |
Correct |
553 ms |
11912 KB |
Output is correct |
4 |
Correct |
691 ms |
16016 KB |
Output is correct |
5 |
Correct |
579 ms |
11540 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
606 ms |
13704 KB |
Output is correct |
2 |
Correct |
560 ms |
11788 KB |
Output is correct |
3 |
Correct |
523 ms |
11712 KB |
Output is correct |
4 |
Correct |
694 ms |
15700 KB |
Output is correct |
5 |
Correct |
595 ms |
11860 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
577 ms |
25352 KB |
Output is correct |
2 |
Correct |
720 ms |
15880 KB |
Output is correct |
3 |
Correct |
703 ms |
14932 KB |
Output is correct |
4 |
Correct |
845 ms |
19468 KB |
Output is correct |
5 |
Correct |
747 ms |
14112 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
842 ms |
16904 KB |
Output is correct |
2 |
Correct |
699 ms |
14540 KB |
Output is correct |
3 |
Correct |
650 ms |
15444 KB |
Output is correct |
4 |
Correct |
850 ms |
19588 KB |
Output is correct |
5 |
Correct |
733 ms |
14928 KB |
Output is correct |