🔴 Can anyone explain me this? How come this output? (C++) [CODE IN DESCRIPTION]

Question

Please explain!

👇🏻

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

Answer 1

In the scope of method add, you introduce New variables a and b, which are not the same as class attributes a and b.
So you are not working with class attributes a and b in this method.
You could now use another Name for the parameters, like p and q as Syrah Algena wrote.
But this is also a very nice example for the use of this-Operator.

Changing the Code to

void add(int a, float b) {
this->a = this->a + a;
this->b = this->b + b;
}

would also work, while the parameters still called a and b.
this->a referres to the class member a,
a referres to Parameter a

Answer 2

Mahima Singh 8 and 8.0 have no difference here because when u adding two float number like
#include <iostream>
using namespace std;
int main(){
float a= 4.5;
float c=a+ a;
cout<<c;
}

U will get 9 not 9.0 so u dint have any issue u can say this is bug but 0.0 and 0 not have any sense its equal hope this example will clear your doubts.

Answer 3

As Syrah Algena said you won't get zero after decimal but if you need it ,here is how to do it .

#include <iostream>
#include <iomanip>
using namespace std;

int main() {
float a=4.0;

cout<<setprecision(1)<<fixed<<a;
return 0;
}

setprecision will define the amount of numbers to print after decimal.

Answer 4

Syrah Algena , Abhay , Abol and G B

Thank you so much each and everyone for clearing my doubts. It was really very helpful! ☺️☺️

Happy coding all of you!!

Answer 5

You have defined same variable when u passing values see this function

void add(int a, float b) {
a = a + a;
b = b + b;
}

Here write p and q u will understood why u getting these values

Answer 6

Syrah Algena ,G B and Abol
#include <iostream>
using namespace std;

class cmplx {

int a;
float b;

public:

cmplx(int x, float y) {
this -> a = x;
this -> b = y;
}

void add(int a, float b) {
this -> a = a + a;
this -> b = b + b;
}

void display() {
cout << "a: " << a;
cout << "\nb: " << b;
}
};

int main() {
cmplx c(5, 2.4);
c.add(2, 4.0);
c.display();
return 0;
}

Why this is printing
a: 4
b: 8 //why not 8.0???

Why it isn't printing 8.0 in b??

Answer 7

G B yes in the given example Compiler getting confused in local and global variables becoz variable names are same a in parameters which she passing and previous defined variable in class .in this case she need to use this keyword