C++ basic doubt regarding function

Question

0.00/5 (No votes)

See more:

C++

#include<iostream> 
using namespace std;
class ComplexNum{
    //public:
    int a,b;
    public:
    void getData(){
        cin >> a >> b;
    }
    
    void getSum(ComplexNum n1, ComplexNum n2, ComplexNum n3){
        n3.a = n2.a + n1.a;
        n3.b = n2.b + n1.b; 
    }
    
 
    void display(){
        cout << "a = " <<a <<" " << "b = " <<b;}
};
int main(){
  ComplexNum n1, n2, n3;
  n1.getData();
  n2.getData();
  n3.getSum(n1,n2,n3);
  n3.display();
    return 0;
}

according to me (I may be wrong) this function is supposed to return n3 which is vector sum of n1 and n2 but it is returning some garbage value. Please help

What I have tried:

i dont know what to do to solve this issue :|

Posted 4-Oct-20 22:42pm

Siddharth Saurav - IIT [BHU]

Updated 5-Oct-20 6:40am

KarstenK

v3

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

CPallini · Accepted Answer · 2020-10-04T22:59:00

The problem is you are modifying a ComplexNum object passed by value (that is the calling code won't see the changes). You should pass it by reference, instead.
Change

Quote:
void getSum(ComplexNum n1, ComplexNum n2, ComplexNum n3){

To

C++

void getSum(const ComplexNum & n1, const ComplexNum & n2, ComplexNum & n3){

in order to fix your code.

Anyway you may also consider overloading the + operator:

C++

#include<iostream>
using namespace std;

class ComplexNum
{
  int a,b;
public:
  void getData()
  {
    cin >> a >> b;
  }

  friend ComplexNum  operator + (const ComplexNum &, const ComplexNum &);

  void display()
  {
        cout << "a = " <<a <<" " << "b = " <<b;
  }
};


ComplexNum operator + (const ComplexNum & c1, const ComplexNum & c2)
{
  ComplexNum r;
  r.a = c1.a + c2.a;
  r.b = c1.b + c2.b;
  return r;
}


int main()
{
  ComplexNum n1, n2, n3;
  n1.getData();
  n2.getData();
  n3 = n1 + n2;
  n3.display();

  return 0;
}