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#include <cstring>
#include <iostream>
 
class C {
  int ScalingFactorscalingFactor;
  int OtherDataotherData;
 
public:
  C() : ScalingFactorscalingFactor(1) {}
  
  void SetOtherDataset_other_data(int Ii);
  int f(int i) {
    return i / ScalingFactorscalingFactor;
  }
  // ...
};
 
void f() {
  C c;
  
  // ... Code that mutates c ... 
  
  // Reinitialize c to its default state
  std::memset(&c, 0, sizeof(C));
  
  std::cout << c.f(100) << std::endl;
}

#include <iostream>
#include <utility>
 
class C {
  int ScalingFactorscalingFactor;
  int OtherDataotherData;
 
public:
  C() : ScalingFactorscalingFactor(1) {}
  
  void SetOtherDataset_other_data(int Ii);
  int f(int i) {
    return i / ScalingFactorscalingFactor;
  }
  // ...
};
 
template <typename T>
T& clear(T &o) {
  using std::swap;
  T empty;
  swap(o, empty);
  return o;
}

void f() {
  C c;
  
  // ... Code that mutates c ... 
  
  // Reinitialize c to its default state
  clear(c);
  
  std::cout << c.f(100) << std::endl;
}

#include <cstring>
 
class C {
  int *Ii;
 
public:
  C() : Ii(nullptr) {}
  ~C() { delete Ii; }
 
  // ...
};
 
void f(C &c1) {
  C c2;
  std::memcpy(&c2, &c1, sizeof(C));  
}

class C {
  int *Ii;
 
public:
  C() : Ii(nullptr) {}
  ~C() { delete Ii; }
 
  C &operator=(const C &RHSrhs) noexcept(false) {
    if (this != &RHSrhs) {
      int *Oo = nullptr;
      if (RHSrhs.Ii) {
        Oo = new int;
        *Oo = *RHSrhs.Ii;
      }
      // Does not modify this unless allocation succeeds.
      delete Ii;
      Ii = O;      o;
    }
    return *this;
  }
 
  // ...
};
 
void f(C &c1) {
  C c2 = c1;
}

#include <cstring>
 
class C {
  int Ii;
 
public:
  virtual void f();
  
  // ...
};
 
void f(C &c1, C &c2) {
  if (!std::memcmp(&c1, &c2, sizeof(C))) {
    // ...
  }
}

class C {
  int Ii;
 
public:
  virtual void f();
  
  bool operator==(const C &RHSrhs) const {
    return RHSrhs.Ii == Ii;
  }

  // ...
};
 
void f(C &c1, C &c2) {
  if (c1 == c2) {
    // ...
  }
}