Submission #898990

# Submission time Handle Problem Language Result Execution time Memory
898990 2024-01-05T10:34:11 Z WLZ Mobile (BOI12_mobile) C++17
0 / 100
346 ms 95728 KB
#include <bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#include "debug.hpp"
#else
#define debug(...)
#endif

using ld = long double;
constexpr ld inf = numeric_limits<long double>::infinity();
constexpr ld eps = 1e-9;

// https://github.com/kth-competitive-programming/kactl/blob/main/content/geometry/Point.h
template<class T>
struct Point {
    typedef Point P;
    T x, y;
    explicit Point(T _x = 0, T _y = 0) : x(_x), y(_y) {}
    P operator+(P p) const { return P(x + p.x, y + p.y); }
    P operator-(P p) const { return P(x - p.x, y - p.y); }
    P operator/(T d) const { return P(x / d, y / d); }
    T dist2() const { return x*x + y*y; }
    ld dist() const { return sqrt((ld) dist2()); }
    P perp() const { return P(-y, x); }
};

// #include "lib/geodeb.h"

int main() {
    ios::sync_with_stdio(false); cin.tie(nullptr);
    // GD_INIT("geodeb.html");

    int n; ld l; cin >> n >> l;
    vector< Point<ld> > p(n);
    for (int i = 0; i < n; i++) {
        cin >> p[i].x >> p[i].y;
        p[i].y = abs(p[i].y);
        // GD_POINT(p[i].x, p[i].y, "black bold");
    }

    vector<ld> ends = {-inf};
    vector< Point<ld> > st = {p[0]};

    for (int i = 1; i < n; i++) {
        // GD_LAYER();
        // GD_POINT(p[i].x, p[i].y, "red bold");
        if (abs(p[i].x - p[i - 1].x) < eps) continue;

        while (true) {
            // GD_LAYER();
            auto q = st.back();
            // GD_SEGMENT(p[i].x, p[i].y, q.x, q.y, "red bold");
            auto m = (p[i] + q) / 2;
            // auto tmp = (q - p[i]).perp() + m;
            // GD_LINE(m.x, m.y, tmp.x, tmp.y, "black");
            ld k = -m.y / (q.x - p[i].x);
            ld x = m.x - k * (q.y - p[i].y);
            // GD_POINT(x, 0, "red bold");
            if (x < ends.back()) {
                st.pop_back(); ends.pop_back();
            } else {
                st.push_back(p[i]); ends.push_back(x);
                break;
            }
        }
    }
    ends.push_back(inf);
    ld ans = 0.0;
    for (int i = 0; i < (int) st.size(); i++) {
        ans = max(ans, (Point<ld>(clamp(ends[i], 0.0l, l), 0) - st[i]).dist());
        ans = max(ans, (Point<ld>(clamp(ends[i + 1], 0.0l, l), 0) - st[i]).dist());
    }
    cout << fixed << setprecision(6) << ans << '\n';

    return 0;
}
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 344 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 348 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 348 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 600 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 600 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 604 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 27 ms 3156 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 34 ms 2908 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 33 ms 10008 KB Output is correct
2 Incorrect 34 ms 2904 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 35 ms 3416 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 40 ms 7492 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 183 ms 47580 KB Output is correct
2 Correct 171 ms 16112 KB Output is correct
3 Correct 166 ms 16216 KB Output is correct
4 Incorrect 213 ms 16212 KB Output isn't correct
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 171 ms 15964 KB Output is correct
2 Incorrect 193 ms 19640 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 222 ms 70200 KB Output is correct
2 Incorrect 196 ms 19240 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 203 ms 19244 KB Output is correct
2 Incorrect 209 ms 22960 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 232 ms 75100 KB Output is correct
2 Incorrect 232 ms 22372 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 234 ms 22376 KB Output is correct
2 Incorrect 240 ms 26184 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 273 ms 81028 KB Output is correct
2 Incorrect 291 ms 25432 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 272 ms 25508 KB Output is correct
2 Incorrect 277 ms 29332 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 346 ms 95728 KB Output is correct
2 Incorrect 343 ms 31760 KB Output isn't correct
3 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 328 ms 31764 KB Output is correct
2 Incorrect 343 ms 38160 KB Output isn't correct
3 Halted 0 ms 0 KB -