#708417 (C++14) No.245 貫け！

• 問題: No.245 貫け！
• ユーザー: t98slider
• 提出日時: 2021-10-21 02:59:09
• 言語: C++14 (gcc 12.3.0 + boost 1.83.0)
• 結果: AC
• 実行時間: 24 ms / 5,000 ms
• コード長: 7,571 bytes
• コンパイル時間: 1,841 ms
• コンパイル使用メモリ: 178,432 KB
• 実行使用メモリ: 4,348 KB
• 最終ジャッジ日時: 2023-10-20 11:17:01
• 合計ジャッジ時間: 3,060 ms
• ジャッジサーバーID （参考情報）: judge11 / judge12

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	2 ms; 4,348 KB
testcase_01	AC	1 ms; 4,348 KB
testcase_02	AC	2 ms; 4,348 KB
testcase_03	AC	1 ms; 4,348 KB
testcase_04	AC	2 ms; 4,348 KB
testcase_05	AC	2 ms; 4,348 KB
testcase_06	AC	1 ms; 4,348 KB
testcase_07	AC	2 ms; 4,348 KB
testcase_08	AC	2 ms; 4,348 KB
testcase_09	AC	3 ms; 4,348 KB
testcase_10	AC	4 ms; 4,348 KB
testcase_11	AC	10 ms; 4,348 KB
testcase_12	AC	24 ms; 4,348 KB
testcase_13	AC	23 ms; 4,348 KB
testcase_14	AC	23 ms; 4,348 KB
testcase_15	AC	24 ms; 4,348 KB
testcase_16	AC	24 ms; 4,348 KB
testcase_17	AC	24 ms; 4,348 KB
testcase_18	AC	24 ms; 4,348 KB
testcase_19	AC	24 ms; 4,348 KB

コンパイルメッセージ

main.cpp: In function 'std::pair<geometry::point, geometry::point> geometry::getCrossPoint(circle, line)':
main.cpp:126:5: warning: control reaches end of non-void function [-Wreturn-type]
  126 |     }
      |     ^

ソースコード

#include <bits/stdc++.h>
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define drep(i,j,n) for(int i=0;i<(int)(n-1);i++)for(int j=i+1;j<(int)(n);j++)
#define trep(i,j,k,n) for(int i=0;i<(int)(n-2);i++)for(int j=i+1;j<(int)(n-1);j++)for(int k=j+1;k<(int)(n);k++)
#define codefor int test;scanf("%d",&test);while(test--)
#define INT(...) int __VA_ARGS__;in(__VA_ARGS__)
#define LL(...) ll __VA_ARGS__;in(__VA_ARGS__)
#define yes(ans) if(ans)printf("yes\n");else printf("no\n")
#define Yes(ans) if(ans)printf("Yes\n");else printf("No\n")
#define YES(ans) if(ans)printf("YES\n");else printf("NO\n")
#define popcount(v) __builtin_popcount(v)
#define vector2d(type,name,h,...) vector<vector<type>>name(h,vector<type>(__VA_ARGS__))
#define vector3d(type,name,h,w,...) vector<vector<vector<type>>>name(h,vector<vector<type>>(w,vector<type>(__VA_ARGS__)))
using namespace std;
using ll = long long;
template<class T> using rpriority_queue = priority_queue<T, vector<T>, greater<T>>;
const int MOD=1000000007;
const int MOD2=998244353;
const int INF=1<<30;
const ll INF2=1LL<<60;
void scan(int& a){scanf("%d",&a);}
void scan(long long& a){scanf("%lld",&a);}
template<class T,class L>void scan(pair<T, L>& p){scan(p.first);scan(p.second);}
template<class T,class U,class V>void scan(tuple<T,U,V>& p){scan(get<0>(p));scan(get<1>(p));scan(get<2>(p));}
template<class T> void scan(T& a){cin>>a;}
template<class T> void scan(vector<T>& vec){for(auto&& it:vec)scan(it);}
void in(){}
template <class Head, class... Tail> void in(Head& head, Tail&... tail){scan(head);in(tail...);}
void print(const int& a){printf("%d",a);}
void print(const long long& a){printf("%lld",a);}
void print(const double& a){printf("%.15lf",a);}
template<class T,class L>void print(const pair<T, L>& p){print(p.first);putchar(' ');print(p.second);}
template<class T> void print(const T& a){cout<<a;}
template<class T> void print(const vector<T>& vec){if(vec.empty())return;print(vec[0]);for(auto it=vec.begin();++it!= vec.end();){putchar(' ');print(*it);}}
void out(){putchar('\n');}
template<class T> void out(const T& t){print(t);putchar('\n');}
template <class Head, class... Tail> void out(const Head& head,const Tail&... tail){print(head);putchar(' ');out(tail...);}
template<class T> void dprint(const T& a){cerr<<a;}
template<class T> void dprint(const vector<T>& vec){if(vec.empty())return;cerr<<vec[0];for(auto it=vec.begin();++it!= vec.end();){cerr<<" "<<*it;}}
void debug(){cerr<<endl;}
template<class T> void debug(const T& t){dprint(t);cerr<<endl;}
template <class Head, class... Tail> void debug(const Head& head, const Tail&... tail){dprint(head);cerr<<" ";debug(tail...);}
ll intpow(ll a, ll b){ ll ans = 1; while(b){ if(b & 1) ans *= a; a *= a; b /= 2; } return ans; }
ll modpow(ll a, ll b, ll p){ ll ans = 1; while(b){ if(b & 1) (ans *= a) %= p; (a *= a) %= p; b /= 2; } return ans; }
ll modinv(ll a, ll m) {ll b = m, u = 1, v = 0;while (b) {ll t = a / b;a -= t * b; swap(a, b);u -= t * v; swap(u, v);}u %= m;if (u < 0) u += m;return u;}
ll updivide(ll a,ll b){return (a+b-1)/b;}
template<class T> void chmax(T &a,const T b){if(b>a)a=b;}
template<class T> void chmin(T &a,const T b){if(b<a)a=b;}

namespace geometry{
    double EPS=1e-10;
    static const int COUNTER_CLOCKWISE = 1;
    static const int CLOCKWISE = -1;
    static const int ONLINE_BACK = 2;
    static const int ONLINE_FRONT = -2;
    static const int ON_SEGMENT = 0;
    struct point{
        double x,y;
        point(double x=0,double y=0): x(x),y(y){}
        point operator + (const point &p){return point(x+p.x,y+p.y);}
        point operator - (const point &p){return point(x-p.x,y-p.y);}
        point operator * (const double k){return point(x*k,y*k);}
        point operator / (const double k){return point(x/k,y/k);}
        double norm(){return sqrt(x*x+y*y);}
        double sqnorm(){return x*x+y*y;}
    };
    void scan(point& p){scanf("%lf %lf",&p.x,&p.y);}
    void print(const point& p){printf("%.15lf %.15lf",p.x,p.y);}
    //ベクトルの内積を計算する
    double dot(point a,point b){return a.x*b.x+a.y*b.y;}
    //ベクトルの外積を計算する
    double cross(point a,point b){return a.x*b.y-a.y*b.x;}
    struct line{
        point p1,p2;
        point base=(p2-p1)/(p2-p1).norm();
        line(point p1,point p2): p1(p1),p2(p2){}
        //pから直線p1p2に垂線を引いた際の交点
        point project(point p){return p1+base*dot(p-p1,base);}
        //pから直線p1p2に対して線対称の位置にある点
        point reflect(point p){return p+(project(p)-p)*2;}
        //直線p1p2に対して点pが反時計回りか時計回りか直線上かを判定する
        int ccw(point p){
            point a=p-p1;
            if(cross(base,a)>EPS)return COUNTER_CLOCKWISE;
            if(cross(base,a)<-EPS)return CLOCKWISE;
            if(dot(base,a)<-EPS)return ONLINE_BACK;
            if((p2-p1).sqnorm()<a.sqnorm())return ONLINE_FRONT;
            return ON_SEGMENT;
        }
    };
    struct circle{
        point c;
        double r;
        circle(point c=point(),double r=0.0): c(c),r(r){}
    };
    //線分s1とs2の交差判定
    bool intersect(line s1,line s2){
        return (s1.ccw(s2.p1)*s1.ccw(s2.p2)<=0);
    }
    //線分s1と線分s2の交点
    point getCrossPoint(line s1,line s2){
        double d1=abs(cross(s2.base,s1.p1-s2.p1));
        double d2=abs(cross(s2.base,s1.p2-s2.p1));
        double t=d1/(d1+d2);
        return s1.p1+(s1.p2-s1.p1)*t;
    }
    //円と直線s1の交点
    //交点が2つの場合はx座標が小さい方が先に出力
    //x座標が同じ場合はy座標が小さいものが先に出力
    //交点が1つの場合は同じ座標が2つ出力
    pair<point,point> getCrossPoint(circle c,line l){
        point pr=l.project(c.c);
        double prl=(pr-c.c).sqnorm();
        if(prl<=c.r*c.r){
            double t=sqrt(c.r*c.r-prl);
            if(abs(l.base.x)<EPS){
                if(l.base.y>0)return make_pair(pr-l.base*t,pr+l.base*t);
                else return make_pair(pr+l.base*t,pr-l.base*t);
            }else{
                if(l.base.x>0)return make_pair(pr-l.base*t,pr+l.base*t);
                else return make_pair(pr+l.base*t,pr-l.base*t);
            }
        }
    }
    //点と点の距離
    double getDistance(point a,point b){return (b-a).norm();}
    //直線と点の距離
    double getDistance(line l,point p){
        return abs(cross(l.p2-l.p1,p-l.p1))/(l.p2-l.p1).norm();
    }
    //線分と点の距離
    double getDistanceSP(line s,point p){
        if(dot(s.p2-s.p1,p-s.p1)<0)return getDistance(s.p1,p);
        if(dot(s.p1-s.p2,p-s.p2)<0)return getDistance(s.p2,p);
        return getDistance(s,p);
    }
    //線分と線分の距離
    double getDistance(line s1,line s2){
        if(intersect(s1,s2))return 0.0;
        return min(min(getDistanceSP(s1,s2.p1),getDistanceSP(s1,s2.p2)),
        min(getDistanceSP(s2,s1.p1),getDistanceSP(s2,s1.p2)));
    }
};

int main(){
    using namespace geometry;
    INT(n);
    vector<line> A;
    vector<pair<int,int>> vec;
    rep(i,n){
        INT(a,b,c,d);
        vec.push_back({a,b});
        vec.push_back({c,d});
        A.push_back(line(point(a,b),point(c,d)));
    }
    int ans=0,cnt;
    drep(i,j,vec.size()){
        line s(point(vec[i].first,vec[i].second),point(vec[j].first,vec[j].second));
        cnt=0;
        rep(k,n){
            cnt+=(intersect(s,A[k]));
        }
        chmax(ans,cnt);
    }
    out(ans);
}