#include <iostream>

class Gerade
{
public:
  Gerade(float anstieg=0, float offset=0)
  : m(anstieg), n(offset)
  {
  }
  float operator()(float x) 
  {
    return m*x + n; 
  }
private:
  float m, n;
};

int main()
{
  Gerade g(0.5, 1);  // g: g(x) = 0.5*x+1
  Gerade h(2, 1.5);

  float y1 = g(3);   // Aufruf operator()
  float y2 = h(3);

  std::cout << y1 <<  ' ' << y2 << '\n';
}