Submission #970993

#	Time	Username	Problem	Language	Result	Execution time	Memory
970993		hgmhc	Mobile (BOI12_mobile)	C++17	100 / 100	393 ms	35448 KiB

mobile

#include <bits/stdc++.h>
using namespace std; using ii = pair<int,int>; using ll = long long; using vi = vector<int>;
#define rep(i,a,b) for (auto i = (a); i <= (b); ++i)
#define per(i,a,b) for (auto i = (b); i >= (a); --i)
#define all(x) begin(x), end(x)
#define siz(x) int((x).size())
#define Mup(x,y) (x = max(x,y))
#define mup(x,y) (x = min(x,y))
#define fi first
#define se second
#define pb push_back
#define dbg(...) fprintf(stderr,__VA_ARGS__)

#pragma region Geometry
#define pt complex<coord_t>
#define TCT template <typename coord_t>

using ld = long double;
const ld PI = acos(-1.0L), EPS = 1e-9;
using Zpt = complex<ll>; using Rpt = complex<ld>;
#define X real()
#define Y imag()

TCT inline coord_t dot(pt u, pt v) { return (conj(u)*v).X; }
TCT inline coord_t cross(pt u, pt v) { return (conj(u)*v).Y; }
TCT inline coord_t orient(pt a, pt b, pt c) { return cross(b-a,c-b); }
TCT inline coord_t abs2(pt u) { return dot(u,u); }
TCT inline      ld abs1(pt u) { return sqrt(ld(abs2(u))); }

TCT istream &operator >> (istream &is, pt &p) {
    coord_t x, y; is >> x >> y; p = {x,y}; return is;
}
namespace std {
    bool operator < (const Zpt &u, const Zpt &v) {
        return u.X == v.X ? u.Y < v.Y : u.X < v.X;
    }
}

#undef pt
#undef TCT
#pragma endregion

using pt = Zpt;

const int N = 1e6+3;
int n;
double l;
pt p[N];

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin >> n >> l;
    rep(i,1,n) cin >> p[i];
    
    auto covered = [](double x) {
        double ptr = 0;
        rep(i,1,n) {
            double dif = sqrt(x*x-p[i].Y*p[i].Y);
            if (p[i].X-dif < ptr+1e-9) Mup(ptr, p[i].X+dif);
        }
        return l < ptr+1e-9;
    };
    
    double a=0, b=1e10, m;
    while (b-a > 1e-3) {
        m = (a+b)/2;
        if (covered(m)) b = m;
        else a = m;
    }
    cout << fixed << setprecision(6) << m;
}

Compilation message (stderr)

mobile.cpp:14: warning: ignoring '#pragma region Geometry' [-Wunknown-pragmas]
   14 | #pragma region Geometry
      | 
mobile.cpp:41: warning: ignoring '#pragma endregion ' [-Wunknown-pragmas]
   41 | #pragma endregion
      |

• Subtask 1: 4 / 4
• Subtask 2: 4 / 4
• Subtask 3: 4 / 4
• Subtask 4: 4 / 4
• Subtask 5: 4 / 4
• Subtask 6: 5 / 5
• Subtask 7: 5 / 5
• Subtask 8: 5 / 5
• Subtask 9: 5 / 5
• Subtask 10: 5 / 5
• Subtask 11: 5 / 5
• Subtask 12: 5 / 5
• Subtask 13: 5 / 5
• Subtask 14: 5 / 5
• Subtask 15: 5 / 5
• Subtask 16: 5 / 5
• Subtask 17: 5 / 5
• Subtask 18: 5 / 5
• Subtask 19: 5 / 5
• Subtask 20: 5 / 5
• Subtask 21: 5 / 5