C++ program to add two complex numbers using class

In this article, we will write a program to add two complex numbers (a1 + ib1) and (a2 + ib2) using class.

For example

Input: 4 + i5 and 8 + i9

Here a1= 4 and a2 = 8. On adding a1 and a2, we get (8 + 4) = 12

Further, b1 = 5 and b2 = 9. On adding b1 and b2, we get (5 + 9) = 14

Output: 9 + i14

Input: 2 + i7 and 10 + i6

Here a1= 2 and a2 = 10. On adding a1 and a2, we get (2 + 10) = 12

Further, b1 = 7 and b2 =6. On adding b1 and b2, we get (7 + 6) = 13

Output: 12 + i13

Class construction

At first, we will create a class for complex numbers. The observation shows that there is a real number(a1) and an imaginary number(b1) in a complex number.

We need two data members to represent the complex numbers.

Below is the class structure:

Constructors

Two constructors will be made to initialize the data members of the class Complex.

• Non - Parameterized constructor

We need a non - parameterized constructor to initialize the default values of the data members to zero.

Below is the structure of non-parameterized constructor

• Parameterized constructor

We need a non-parameterized constructor to initialize the data members to the value passed by the main function.

Below is the structure of parameterized constructor

Algorithm

For adding two complex numbers, we will make two objects of the Complex class and initialize them with the values. After that, we will make a third object that will store the result.

C++ code

Output

```Complex number 1 : 4 + i5
Complex number 2 : 8 + i9
Sum of complex number : 12 + i14

Complex number 1 : 2 + i7
Complex number 2 : 10 + i6
Sum of complex number : 12 + i13

Time complexity
The time complexity is O(1) as we have to call the function addComplexNumber() to add the two complex numbers.
```