func_code_string: #include <bits/stdc++.h>   using namespace std;   vector<pair<double, double> > vec;   double x[10], y[10];   int cross(pair<double, double> a, pair<double, double> b,             pair<double, double> c) {     double re = (a.first - c.first) * (b.second - c.second);     re -= (a.second - c.second) * (b.first - c.first);     if (fabs(re) < 1e-8) return 0;     return re > 0 ? 1 : -1;   }   bool work() {     double x0, y0, d, xb, yb, xc, yc, xa, ya, xd, yd;     int i;     x0 = x[1] * 2 - x[2];     y0 = y[1] * 2 - y[2];     d = x0 * (y[1] - y[3]) + x[1] * (y[3] - y0) + x[3] * (y0 - y[1]);     d *= 2;     xb = (x0 * x0 + y0 * y0) * (y[1] - y[3]);     xb += (x[1] * x[1] + y[1] * y[1]) * (y[3] - y0);     xb += (x[3] * x[3] + y[3] * y[3]) * (y0 - y[1]);     xb /= d;     yb = (x0 * x0 + y0 * y0) * (x[3] - x[1]);     yb += (x[1] * x[1] + y[1] * y[1]) * (x0 - x[3]);     yb += (x[3] * x[3] + y[3] * y[3]) * (x[1] - x0);     yb /= d;     xc = 2 * x[1] - xb;     yc = 2 * y[1] - yb;     xa = 2 * x[3] - xb;     ya = 2 * y[3] - yb;     xd = 2 * x[2] - xc;     yd = 2 * y[2] - yc;     vec.clear();     vec.push_back(make_pair(xa, ya));     vec.push_back(make_pair(xd, yd));     vec.push_back(make_pair(xc, yc));     vec.push_back(make_pair(xb, yb));     for (i = 0; i < 4; i++)       if (cross(vec[i], vec[(i + 1) % 4], vec[(i + 2) % 4]) *               cross(vec[i], vec[(i + 1) % 4], vec[(i + 3) % 4]) <=           0)         return false;     printf( YES n );     for (i = 0; i < 4; i++) printf( %.10f %.10f  , vec[i].first, vec[i].second);     printf(  n );     return true;   }   int main() {     int T, i;     scanf( %d , &T);     while (T--) {       for (i = 1; i <= 3; i++) scanf( %lf%lf , &x[i], &y[i]);       if ((x[1] - x[3]) * (y[2] - y[3]) == (y[1] - y[3]) * (x[2] - x[3])) {         printf( NO n n );         continue;       }       if (work()) continue;       swap(x[1], x[2]);       swap(y[1], y[2]);       if (work()) continue;       swap(x[1], x[3]);       swap(y[1], y[3]);       if (work()) continue;       printf( NO n n );     }   }   