Need help creating a conversion function

So i have the following classes:

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 class Person {
 public:
	Person(string n, int a) {
		name = n;
		age = a;
	}

  
 private:
	string name;
	int age;
 }; 

 class Car{
 public:
	Car(string m, Person* ps, Person* pss) {
		model = m;
		owner = ps;
		driver = pss;
	}
	
 private:
	string model;
	Person* owner;
	Person* driver;
 };


I don't want to post the whole code, so later down the line i have:

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 cin >> model >> owner >> driver;
 Person* o = owner;
 Person* d = driver;
 Car* a = new Car(model, o, d);
 cars.push_back(a);


"cars" is a vector. I want to read 3 strings - model owner driver and write them down into the cars vector. The problem is that i get the following error:
No suitable conversion function from "std:string" to "Person*" exists.
What function do i need to write in order to assign a string variable to the owner and driver objects that i have in my Car class?


the pointers is a really bad approach -- avoid dynamic memory if you can (and, you can here!) That aside, what you need is a setter for owner and driver.

what you need is for 'person' object to have a constructor or setter to assign its private member string to owner/driver after line 3 above. eg
o[0].setsomething(owner);
d[0].setsomething(driver);

you can almost do it, but person ctor expects an age you don't have. if you read in the ages, you can do it as-is:
person* o = new person(owner, oage);
person* d = new person(driver, dage);

what you have currently is trying to put a string into a pointer, which won't work. you need to allocate the owner and driver.
Last edited on
Hello underfree22,

Jonnin has said most of what I would have said.

So consider this:
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#include <iostream>
#include <string>
#include <vector>

class Person
{
	public:
		Person(std::string n, int a)
		{
			name = n;
			age = a;
		}

	private:
		std::string name;
		int age;
};

class Car
{
	public:
		Car(std::string m, std::string ps, std::string pss)
		{
			model = m;
			owner = ps;
			driver = pss;
		}

	private:
		std::string model;
		std::string owner;
		std::string driver;
};

int main()
{
	std::vector<Car> cars;

	std::string model, owner, driver;

	std::cout << "\n Enter model name: ";
	std::getline(std::cin, model);

	std::cout << "\n Enter owner name: ";
	std::getline(std::cin, owner);
	
	std::cout << "\n Enter driver: ";
	std::getline(std::cin, driver);


	cars.emplace_back(model, owner, driver);

	return 0;  // <--- Not required, but makes a good break point.
}

I used "std::getline" because any of those variables could have a space in it.

Using the "emplace_back" this makes use of the overloaded ctor to first create an object of the class before storing it in the vector. A bit easier.

In the class I changed the pointers to "std::stings" because I know of no way of converting a "std::string" to a "Person *".

Without the rest of the code or a better explaination of the program I am not sure what you are trying to do or why you feel that "owner" and "driver" need to be "Person *"s.

Hope that helps,

Andy
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