func_code_string: #include <bits/stdc++.h>   using namespace std;   const double pi = acos(-1.0);   const double eps = 1e-11;   const int inf = 0x7FFFFFFF;   template <class T>   inline void checkmin(T &a, T b) {     if (b < a) a = b;   }   template <class T>   inline void checkmax(T &a, T b) {     if (b > a) a = b;   }   template <class T>   inline T sqr(T x) {     return x * x;   }   template <class T>   void show(T a, int n) {     for (int i = 0; i < n; ++i) cout << a[i] <<    ;     cout << endl;   }   template <class T>   void show(T a, int r, int l) {     for (int i = 0; i < r; ++i) show(a[i], l);     cout << endl;   }   int sgn(double x) { return x < -eps ? -1 : x > eps; }   int main() {     double y1, y2, yw, xb, yb, r;     while (cin >> y1 >> y2 >> yw >> xb >> yb >> r) {       if (sgn(y2 - y1 - 2 * r) < 0) {         puts( -1 );         continue;       } else {         double y = (y1 + r), yyw = yw - r;         double ax = (yyw - y) / (yyw - y + yyw - yb) * xb;         double ds = (y2 - y) * ax / (sqrt(sqr(ax) + sqr(yyw - y)));         if (sgn(ds - r) <= 0) {           puts( -1 );           continue;         }         printf( %.12lf n , ax);       }     }     return 0;   }   