func_code_string: #include <bits/stdc++.h>   using namespace std;   const double eps = 1e-8;   struct Point {     double x, y;     Point(double x = 0, double y = 0) : x(x), y(y) {}   };   double Dot(Point A, Point B) { return A.x * B.x + A.y * B.y; }   double Length(Point A) { return sqrt(Dot(A, A)); }   double Angle(Point A, Point B) {     return acos(Dot(A, B) / Length(A) / Length(B));   }   Point Normal(Point A) {     double L = Length(A);     return Point(-A.y / L, A.x / L);   }   double Cross(Point A, Point B) { return A.x * B.y - A.y * B.x; }   Point operator+(Point A, Point B) { return Point(A.x + B.x, A.y + B.y); }   Point operator-(Point A, Point B) { return Point(A.x - B.x, A.y - B.y); }   Point operator*(Point A, double p) { return Point(A.x * p, A.y * p); }   Point operator/(Point A, double p) { return Point(A.x / p, A.y / p); }   int dcmp(double x) {     if (fabs(x) < eps) return 0;     return x < 0 ? -1 : 1;   }   bool operator<(const Point &a, const Point &b) {     return a.x < b.x || (a.x == b.x && a.y < b.y);   }   bool operator==(const Point &a, const Point &b) {     return dcmp(a.x - b.x) == 0 && dcmp(a.y - b.y) == 0;   }   double GetAngleByLength(double a, double b, double c) {     double cosA = (b * b + c * c - a * a) / (b * c * 2);     return acos(cosA);   }   Point Rotate(Point A, double rad) {     return Point(A.x * cos(rad) - A.y * sin(rad),                  A.x * sin(rad) + A.y * cos(rad));   }   Point GetLineIntersection(Point P, Point v, Point Q, Point w) {     Point u = P - Q;     double t = Cross(w, u) / Cross(v, w);     return P + v * t;   }   Point R;   Point v;   double solve(Point P, Point vP, Point Q, Point vQ) {     auto X = GetLineIntersection(P, vP, R, v);     auto Y = GetLineIntersection(Q, vQ, R, v);     return Length(P - X) + Length(X - Y) + Length(Q - Y);   }   int main() {     double a, b, c, x1, y1, x2, y2;     cin >> a >> b >> c >> x1 >> y1 >> x2 >> y2;     if (a == 0 || b == 0) {       double ans = fabs(x1 - x2) + fabs(y1 - y2);       printf( %.10f n , ans);       return 0;     }     R.x = 0;     R.y = -c / b;     v = Point(b, -a);     double ans = fabs(x1 - x2) + fabs(y1 - y2);     ans = min(ans, solve(Point(x1, y1), Point(1, 0), Point(x2, y2), Point(1, 0)));     ans = min(ans, solve(Point(x1, y1), Point(1, 0), Point(x2, y2), Point(0, 1)));     ans = min(ans, solve(Point(x1, y1), Point(0, 1), Point(x2, y2), Point(1, 0)));     ans = min(ans, solve(Point(x1, y1), Point(0, 1), Point(x2, y2), Point(0, 1)));     printf( %.10f n , ans);     return 0;   }   