Submission #942890

#	Time	Username	Problem	Language	Result	Execution time	Memory
942890		huutuan	Nicelines (RMI20_nicelines)	C++14	84.04 / 100	43 ms	704 KiB

nicelines

#include "nice_lines.h"

#include <bits/stdc++.h>

using namespace std;

template<class T>
struct Point{
   T x, y;
   Point (T _x=0, T _y=0){
      x=_x; y=_y;
   }
   bool operator<(Point a){ return tie(x, y)<tie(a.x, a.y); }
   bool operator==(Point a){ return tie(x, y)==tie(a.x, a.y); }
   Point operator+(Point a){ return Point(x+a.x, y+a.y); }
   Point operator-(Point a){ return Point(x-a.x, y-a.y); }
   Point operator*(T a){ return Point(x*a, y*a); }
   Point operator/(T a){ return Point(x/a, y/a); }
   T dot(Point a){ return x*a.x+y*a.y; }
   T dot(Point a, Point b){ return (a-*this).dot(b-*this); }
   T cross(Point a){ return x*a.y-y*a.x; }
   T cross(Point a, Point b){ return (a-*this).cross(b-*this); }
   T dist2(){ return x*x+y*y; }
   long double dist(){ return sqrt(dist2()); }
};

const long double eps=1e-7;
using pt=Point<long double>;

long double line_point_dist(pt a, pt b, pt c){
   return abs(a.cross(b, c))/(a-b).dist();
}

mt19937 rng(69420);

long double rand(long double l, long double r){
   return uniform_real_distribution<long double>(l, r)(rng);
}

pair<int, int> line_from_points(pt a, pt b){
   long double slope=round((b.y-a.y)/(b.x-a.x));
   return {(int)(round(slope)), (int)(round(a.y-a.x*slope))};
}

void solve(int subtask_id, int N) {
   auto f=[&](long double t) -> long double {
      return query(3e4, t);
   };
   vector<int> va, vb;
   auto dnc=[&](auto self, long double l, long double r, long double fl, long double fr){
      long double mid=(l+r)/2;
      long double fmid=f(mid);
      if (abs((fl+fr)/2-fmid)<eps) return;
      if ((r-l)<1){
         long double c=(f(r+0.1)-fr-fl+f(l-0.1))/2;
         long double d=sqrtl(max<long double>(0.0, 0.1*0.1-c*c));
         int a=round(d/c);
         if (mid<-eps) a=-a;
         int b=round(mid-(3e4)*a);
         va.push_back(a);
         vb.push_back(b);
         return;
      }
      self(self, l, mid, fl, fmid);
      self(self, mid, r, fmid, fr);
      return;
   };
   long double l=-3.3e8+rand(1, 10), r=3.3e8-rand(1, 10);
   dnc(dnc, l, r, f(l), f(r));
   the_lines_are(va, vb);
}

• Subtask 1: 11 / 11
• Subtask 2: 13 / 13
• Subtask 3: 7 / 7
• Subtask 4: 13.8881329445 / 19
• Subtask 5: 21.022306730300002 / 23
• Subtask 6: 18.132871431599998 / 27