Default constructor c++

Question

How do you perform a default constructor that has a default value of 0 to the variable of m_throttle(for example)?? Thanks

Answer 1

Charmaine Labastida At this point, I'm still very unsure what you need to achieve, but I've tweaked a bit of your code to hopefully create something which works according to your description.

https://code.sololearn.com/chNVZLXpwxfY/?ref=app

Answer 2

A default constructor is a constructor called with no arguments. If you want it to initialize m_throttle to 0, then

myClass() { m_throttle = 0; }

or using initialization list

myClass() : m_throttle(0) {}

Answer 3

Well... if you're already using class member initialisation

int m_throttle {0};

m_throttle is already 0 and there should be no need to explicitly set it to 0 using a setter (although you may).

Your code works as long as you define your setter.

void Car::setThrottle(int n) {
m_throttle = n;
}

and should be called as:

setThrottle(0);

if you want to set m_throttle to 0.

Answer 4

i need to create a virtual method serialize(overriding the Vehicle virtual serialize)
my output should be :
“Car: Throttle: throttle @ [lat, lon, alt]”
//lat, lon, alt are variables

so far what i have is:

Car.h

class Car : public Vehicle {
private:
virtual void Serialize(ostream& os);
}

Car.cpp

void Car::Serialize(ostream& os) {
os << “Car: Throttle: throttle @ [“;
//what to put inside???
}

Vehicle.h

class Vehicle {
private:
virtual void serialize(ostream& os);
}

Answer 5

does this work?

Car.h

class Car {
public:
Car();

private:
int m_throttle {0};
};

Car.cpp

Car::Car() {
cout << “Car: Default-ctor” << endl;
setThrottle(m_throttle);
}