Submission #942728

#	Time	Username	Problem	Language	Result	Execution time	Memory
942728		vjudge1	Nicelines (RMI20_nicelines)	C++14	24 / 100	99 ms	444 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-5;
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) {
   if (N==1){
      pt a, b;
      {
         pt l(-1e12, -rand(0, 69420));
         pt r(1e12, rand(0, 69420));
         for (int _=0; _<125; ++_){
            pt m1=l+(r-l)/3, m2=l+(r-l)/3*2;
            long double t1=query(m1.x, m1.y), t2=query(m2.x, m2.y);
            if (t1<t2) r=m2;
            else l=m1;
         }
         a=l;
      }
      {
         pt l(-rand(0, 69420), -1e12);
         pt r(rand(0, 69420), 1e12);
         for (int _=0; _<125; ++_){
            pt m1=l+(r-l)/3, m2=l+(r-l)/3*2;
            long double t1=query(m1.x, m1.y), t2=query(m2.x, m2.y);
            if (t1<t2) r=m2;
            else l=m1;
         }
         b=l;
      }
      auto line=line_from_points(a, b);
      the_lines_are({line.first}, {line.second});
      return;
   }
   if (N==2){
      vector<pt> v;
      for (int i=1; i<=10; ++i){
         pt l(-1e12, -rand(0, 69420));
         pt r(1e12, rand(0, 69420));
         for (int _=0; _<125; ++_){
            pt m1=l+(r-l)/3, m2=l+(r-l)/3*2;
            long double t1=query(m1.x, m1.y), t2=query(m2.x, m2.y);
            if (t1<t2) r=m2;
            else l=m1;
         }
         v.push_back(l);
      }
      for (int i=1; i<=10; ++i){
         pt l(-1e12, rand(0, 69420));
         pt r(1e12, -rand(0, 69420));
         for (int _=0; _<125; ++_){
            pt m1=l+(r-l)/3, m2=l+(r-l)/3*2;
            long double t1=query(m1.x, m1.y), t2=query(m2.x, m2.y);
            if (t1<t2) r=m2;
            else l=m1;
         }
         v.push_back(l);
      }
      for (int i=1; i<=10; ++i){
         pt l(-rand(0, 69420), -1e12);
         pt r(rand(0, 69420), 1e12);
         for (int _=0; _<125; ++_){
            pt m1=l+(r-l)/3, m2=l+(r-l)/3*2;
            long double t1=query(m1.x, m1.y), t2=query(m2.x, m2.y);
            if (t1<t2) r=m2;
            else l=m1;
         }
         v.push_back(l);
      }
      for (int i=1; i<=10; ++i){
         pt l(rand(0, 69420), -1e12);
         pt r(-rand(0, 69420), 1e12);
         for (int _=0; _<125; ++_){
            pt m1=l+(r-l)/3, m2=l+(r-l)/3*2;
            long double t1=query(m1.x, m1.y), t2=query(m2.x, m2.y);
            if (t1<t2) r=m2;
            else l=m1;
         }
         v.push_back(l);
      }
      for (int i=0; i<2; ++i) for (int j=i+1; j<2; ++j){
         vector<pt> v1, v2;
         for (int k=0; k<(int)v.size(); ++k){
            if (abs(v[i].cross(v[j], v[k]))<eps){
               v1.push_back(v[k]);
            }else{
               v2.push_back(v[k]);
            }
         }
         if ((int)v1.size()<2 || (int)v2.size()<2) continue;
         bool check=1;
         for (int k=0; k<(int)v2.size(); ++k) check&=abs(v2[0].cross(v2[1], v2[k]))<eps;
         if (!check) continue;
         auto line1=line_from_points(v1[0], v1[1]);
         auto line2=line_from_points(v2[0], v2[1]);
         the_lines_are({line1.first, line2.first}, {line1.second, line2.second});
         return;
      }
      assert(false);
   }
}

• Subtask 1: 11 / 11
• Subtask 2: 13 / 13
• Subtask 3: 0 / 7
• Subtask 4: 0 / 19
• Subtask 5: 0 / 23
• Subtask 6: 0 / 27