답안 #681414

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
681414 2023-01-13T03:48:21 Z Kamisama 먼 별 (KOI16_dist) C++14
100 / 100
229 ms 3156 KB
#include <iostream>
#include <cstdlib>
#include <climits>
#include <algorithm>
using namespace std;
const int MAXN = 3e4 + 7;

struct Star {
    long long x, y, dx, dy;
    Star(long long x=0, long long y=0, long long dx=0, long long dy=0)
        : x(x), y(y), dx(dx), dy(dy) {}

    Star operator-(const Star &other) const {
        return Star(x - other.x, y - other.y);
    }

    long long operator%(const Star &other) const {
        return x * other.y - y * other.x;
    }
};

int n, t, hull_size;
Star a[MAXN], p[MAXN];
Star convex_hull[MAXN];

int ccw(const Star &A, const Star &B, const Star &C) {
    long long res = A % B + B % C + C % A;
    return (res > 0) - (res < 0);
}

long long get_distance(const Star &A, const Star &B) {
    long long dx = A.x - B.x;
    long long dy = A.y - B.y;
    return dx * dx + dy * dy;
}

long long solve(int k) {
    for(int i = 1; i <= n; i++) {
        p[i] = Star(a[i].x + k * a[i].dx, a[i].y + k * a[i].dy);
    }

    swap(p[1], *min_element(p + 1, p + n + 1, [](const Star &A, const Star &B) {
        return A.x < B.x || (A.x == B.x && A.y < B.y);
    }));
    sort(p + 2, p + n + 1, [](const Star &A, const Star &B) {
        int not_linear = ccw(p[1], A, B);
        if(not_linear) return not_linear > 0;
        return get_distance(p[1], A) < get_distance(p[1], B);
    });

    hull_size = 0;
    for(int i = 1; i <= n; i++) {
        while(hull_size >= 2 && ccw(convex_hull[hull_size - 1], convex_hull[hull_size], p[i]) <= 0){
            hull_size--;
        }
        convex_hull[++hull_size] = p[i];
    }

    long long res = 0;
    for(int i = 1, j = 1; i <= hull_size; i++) {
        while(j < hull_size && (convex_hull[i + 1] - convex_hull[i]) % (convex_hull[j + 1] - convex_hull[j]) >= 0) {
            res = max(res, get_distance(convex_hull[i], convex_hull[j]));
            j++;
        }
        res = max(res, get_distance(convex_hull[i], convex_hull[j]));
    }

    return res;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    cin >> n >> t;
    for(int i = 1; i <= n; i++) cin >> a[i].x >> a[i].y >> a[i].dx >> a[i].dy;

    int l = 0, r = t - 1;
    while(l <= r) {
        int m = (l + r) / 2;
        if(solve(m) > solve(m + 1)) l = m + 1;
        else r = m - 1;
    }

    cout << l << '\n' << solve(l);

    return 0;
}
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 3028 KB Output is correct
2 Correct 2 ms 3028 KB Output is correct
3 Correct 1 ms 3028 KB Output is correct
4 Correct 2 ms 3028 KB Output is correct
5 Correct 2 ms 3028 KB Output is correct
6 Correct 2 ms 3028 KB Output is correct
7 Correct 2 ms 3028 KB Output is correct
8 Correct 2 ms 3088 KB Output is correct
9 Correct 1 ms 3028 KB Output is correct
10 Correct 2 ms 3028 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 3028 KB Output is correct
2 Correct 2 ms 3028 KB Output is correct
3 Correct 1 ms 3028 KB Output is correct
4 Correct 2 ms 3028 KB Output is correct
5 Correct 2 ms 3028 KB Output is correct
6 Correct 2 ms 3028 KB Output is correct
7 Correct 2 ms 3028 KB Output is correct
8 Correct 2 ms 3088 KB Output is correct
9 Correct 1 ms 3028 KB Output is correct
10 Correct 2 ms 3028 KB Output is correct
11 Correct 6 ms 3028 KB Output is correct
12 Correct 6 ms 3028 KB Output is correct
13 Correct 5 ms 3028 KB Output is correct
14 Correct 6 ms 3028 KB Output is correct
15 Correct 6 ms 3028 KB Output is correct
16 Correct 8 ms 3028 KB Output is correct
17 Correct 7 ms 3156 KB Output is correct
18 Correct 5 ms 3028 KB Output is correct
19 Correct 5 ms 3140 KB Output is correct
20 Correct 7 ms 3028 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 58 ms 3116 KB Output is correct
2 Correct 58 ms 3128 KB Output is correct
3 Correct 53 ms 3120 KB Output is correct
4 Correct 44 ms 3124 KB Output is correct
5 Correct 54 ms 3028 KB Output is correct
6 Correct 67 ms 3136 KB Output is correct
7 Correct 44 ms 3116 KB Output is correct
8 Correct 28 ms 3028 KB Output is correct
9 Correct 54 ms 3028 KB Output is correct
10 Correct 55 ms 3028 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 3028 KB Output is correct
2 Correct 2 ms 3028 KB Output is correct
3 Correct 1 ms 3028 KB Output is correct
4 Correct 2 ms 3028 KB Output is correct
5 Correct 2 ms 3028 KB Output is correct
6 Correct 2 ms 3028 KB Output is correct
7 Correct 2 ms 3028 KB Output is correct
8 Correct 2 ms 3088 KB Output is correct
9 Correct 1 ms 3028 KB Output is correct
10 Correct 2 ms 3028 KB Output is correct
11 Correct 6 ms 3028 KB Output is correct
12 Correct 6 ms 3028 KB Output is correct
13 Correct 5 ms 3028 KB Output is correct
14 Correct 6 ms 3028 KB Output is correct
15 Correct 6 ms 3028 KB Output is correct
16 Correct 8 ms 3028 KB Output is correct
17 Correct 7 ms 3156 KB Output is correct
18 Correct 5 ms 3028 KB Output is correct
19 Correct 5 ms 3140 KB Output is correct
20 Correct 7 ms 3028 KB Output is correct
21 Correct 58 ms 3116 KB Output is correct
22 Correct 58 ms 3128 KB Output is correct
23 Correct 53 ms 3120 KB Output is correct
24 Correct 44 ms 3124 KB Output is correct
25 Correct 54 ms 3028 KB Output is correct
26 Correct 67 ms 3136 KB Output is correct
27 Correct 44 ms 3116 KB Output is correct
28 Correct 28 ms 3028 KB Output is correct
29 Correct 54 ms 3028 KB Output is correct
30 Correct 55 ms 3028 KB Output is correct
31 Correct 207 ms 3028 KB Output is correct
32 Correct 229 ms 3028 KB Output is correct
33 Correct 197 ms 3148 KB Output is correct
34 Correct 199 ms 3028 KB Output is correct
35 Correct 220 ms 3116 KB Output is correct
36 Correct 168 ms 3132 KB Output is correct
37 Correct 172 ms 3028 KB Output is correct
38 Correct 113 ms 3124 KB Output is correct
39 Correct 162 ms 3028 KB Output is correct
40 Correct 210 ms 3120 KB Output is correct
41 Correct 183 ms 3028 KB Output is correct
42 Correct 211 ms 3124 KB Output is correct