Describe the concept of constructor with default argument with suitable example.

Describe the concept of constructor with default argument with suitable example.
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1 Answer

Answer :

Definition: The constructor where we can assign default values for one or more parameters at the time of function declaration is called as constructor with default argument


Example:

class complex

{

float real, img ;

public:

complex (float r,floati=0.0 )

{

real=r;

img=I;

}

void display()

{

cout<< real<<”+”<<img<<”i”<<endl;

}

}

void main()

{

complex c1(5.0);

complex c2(2.0,3.0);

cout<<”complex c1:\n”;

c1.display();

cout<<”complex c2:\n”;

c2.display();

getch();

}


These corresponding parameters are omitted in the call to the constructor For example the constructor complex() can be declared as follows: complex (float real, float img=0.0); Here, if default value of the argument img is set to zero, then the statement: complex c(5.0); Assigns the value 5.0 to real and 0.0 to img (by default). complex c(2.0,3.0); Assigns 2.0 to real and 3.0 to img., because the actual parameters, when specified overrides the default value.
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