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| #include <iostream>
#include <cstdio>
#include <cctype>
#include <algorithm>
#include <cstring>
#include <cmath>
using namespace std;
using longs = long long;
using uint = unsigned;
inline int nextInt()
{
int x = 0, f = 1, ch = getchar();
while (!isdigit(ch)) if (ch == '-') f = -1, ch = getchar();
while (isdigit(ch)) x = x * 10 + ch - 48, ch = getchar();
return x * f;
}
namespace Geo
{
using number = long double;
const number eps = 1e-8;
int compareTo(number x) {return x < -eps ? -1 : x > eps;}
int compareTo(number a, number b) {return compareTo(a-b);}
struct point
{
number x, y;
point() = default;
point(number x, number y) : x(x), y(y) {}
point operator +(const point &rhs) const {return {x + rhs.x, y + rhs.y};}
point operator -(const point &rhs) const {return {x - rhs.x, y - rhs.y};}
number operator *(const point &rhs) const {return x * rhs.x + y * rhs.y;}
point operator *(const number rhs) const {return {rhs * x, rhs * y};}
point operator /(const number rhs) const {return {x / rhs, y / rhs};}
point &operator +=(const point& rhs) {x += rhs.x; y += rhs.y; return *this;}
point &operator -=(const point& rhs) {x -= rhs.x; y -= rhs.y; return *this;}
point &operator *=(const number rhs) {x *= rhs; y *= rhs; return *this;}
point &operator /=(const number rhs) {x /= rhs; y /= rhs; return *this;}
bool operator ==(const point &rhs) const {return x == rhs.x && y == rhs.y;}
bool operator !=(const point &rhs) const {return !(rhs == *this);}
number dot(const point &rhs) const {return x * rhs.x + y * rhs.y;}
number cross(const point &rhs) const {return rhs.y * x - rhs.x * y;}
auto length() const {return sqrt(dot(*this));}
auto distance(const point &b) const {return (*this - b).length();}
auto distance(const point &ls, const point &rs) const
{return fabs((ls - *this).cross(rs - *this)) / ls.distance(rs);}
point normal() const {return (x || y) ? *this / length() : point(0, 0);}
auto angle() const {return atan2(y, x);}
point rotate(number a) const
{number c = cos(a), s = sin(a); return {c * x - s * y, s * x + c * y};}
point perpendicular() const {return {-y, x};}
point symmetry() const {return {-x, -y};}
number square() const { return x * x + y * y; }
};
struct line
{
point s, t;
line() = default;
line(number a, number b, number x, number y) : s(a, b), t(x, y) {}
line(const point &s, const point &t) : s(s), t(t) {}
};
int onLeft(point p, line l)
{
number xx = (l.t - l.s).cross(p - l.s);
return compareTo(xx);
}
}
using point = Geo::point;
using number = Geo::number;
using Geo::compareTo;
point p[25];
number d[25];
int main()
{
ios::sync_with_stdio(false);
std::cin.tie(nullptr);
std::cout.tie(nullptr);
int t;
cin >> t;
while (t --)
{
for (int i = 0; i < 20; ++ i)
cin >> p[i].x >> p[i].y;
d[0] = p[0].distance(p[19]);
for (int i = 1; i < 20; ++ i)
d[i] = p[i].distance(p[i - 1]);
int xp = 0; number xx = 0;
for (int i = 0; i < 20; ++ i)
if (compareTo(d[i], xx) > 0) xx = d[i], xp = i;
auto hand = Geo::line(p[xp], p[(xp + 19) % 20]);
auto &ff = p[(xp + 18) % 20], &bb = p[(xp + 1) % 20];
if (Geo::onLeft(ff, hand) > 0)
if (compareTo(d[(xp + 1) % 20], d[(xp + 19) % 20]) > 0)
cout << "left" << endl;
else cout << "right" << endl;
else
if (compareTo(d[(xp + 1) % 20], d[(xp + 19) % 20]) > 0)
cout << "right" << endl;
else cout << "left" << endl;
}
return 0;
}
|
