問題文:404 Not Found
ライブラリゲー。ccwやintersectSS,crosspointはspaghetti sourceのもの。
本選でのこれの配点があんまり高くないのは悲しいよね。
気をつけるべきは「0,0,0,1」とかの入力を見逃さないこと。
#include <iostream> #include <vector> #include <complex> using namespace std; static const double EPS = 1e-12; #define rep(i,n) for(int i=0;i<n;i++) const double INF = 1e12; typedef complex<double> P,point; namespace std {bool operator < (const P& a, const P& b) {return real(a) != real(b) ? real(a) < real(b) : imag(a) < imag(b);}} double cross(const P& a, const P& b) {return imag(conj(a)*b);} double dot(const P& a, const P& b) {return real(conj(a)*b);} struct L : public vector<P> {L(const P &a, const P &b) {push_back(a); push_back(b);}}; int ccw(P a, P b, P c) { b -= a; c -= a; if (cross(b, c) > 0) return +1; // counter clockwise if (cross(b, c) < 0) return -1; // clockwise if (dot(b, c) < 0) return +2; // c--a--b on line if (norm(b) < norm(c)) return -2; // a--b--c on line return 0; } bool intersectSS(const L &s, const L &t) { return ccw(s[0],s[1],t[0])*ccw(s[0],s[1],t[1]) <= 0 && ccw(t[0],t[1],s[0])*ccw(t[0],t[1],s[1]) <= 0; } P crosspoint(const L &l, const L &m) { double A = cross(l[1] - l[0], m[1] - m[0]); double B = cross(l[1] - l[0], l[1] - m[0]); if (abs(A) < EPS && abs(B) < EPS) return m[0]; // same line return m[0] + B / A * (m[1] - m[0]); } double getArea(P a, P b , P c){ b-=a, c-=a; return fabs( b.real() * c.imag() - c.real() * b.imag() ) / 2.0; } int main(){ double a,b,c,d; while(cin >> a >> b >> c >> d , a || b || c || d){ L one = L(P(a,b),P(c,d)); cin >> a >> b >> c >> d; L two = L(P(a,b),P(c,d)); cin >> a >> b >> c >> d; L three = L(P(a,b),P(c,d)); double ret = 0; if(intersectSS(one,two) && intersectSS(two,three) && intersectSS(one,three)){ ret = getArea( crosspoint(one,two) , crosspoint(two,three) , crosspoint(one,three) ); } if(ret >= 1900000){ cout << "dai-kichi" << endl; }else if(ret >= 1000000){ cout << "chu-kichi" << endl; }else if(ret >= 100000){ cout << "kichi" << endl; }else if(ret > 0){ cout << "syo-kichi" << endl; }else{ cout << "kyo" << endl; } } }