Consider a c++ template funtion
template<class T>
T& Add(T a, T b){return a+b ;}
if this function is called as
T c = Add("SAM", "SUNG");
what will happen? What is the problem in the template
declaration/ How to solve the problem.
- 7 Answers
- 14907 Views
- LG, Samsung, I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / sg
"SAM" and "SUNG" will be considered as const char * and
there will be an compile time error. To over come this we
can call the fun as
string c = Add<string>("SAM","SUNG");
as the string class as '+' operator overloaded and it will
add the two string.
| Is This Answer Correct ? | 15 Yes | 1 No |
Answer / tathagata chakraborty
None of the other answers are coming to the point of this
question.They r all wrong.
right answer is the code will crash while returning frm Add
(). bcause the function is returning a local variable of
type T i.e. a+b as a refference. u cannont return a local
variable as refference bcause that will go out of scope as
soon as the function returns.
| Is This Answer Correct ? | 11 Yes | 3 No |
Answer / prasad
i will provide error.
declare template function as,
T Add(T a, T b){return a+b ;}
| Is This Answer Correct ? | 10 Yes | 4 No |
Answer / skc
The error is adding Two pointers isn't alowed in C/C++.
The compiler imlicitly treats "SAM" as const char*. We need
to write a function with "explicit" keyword declaration like
explicit char * Add (const char* x1, const char* x2)
{
// check for null pointers.
// allocate strlen(x1)+strlen(x2)+1 using malloc
// say char*a1 = malloc...;
// check if malloc returns null..take corrective actions
// strcpy (a1, x1);
// strcat (a1, x2);
//strcat (a1, '\0');
return a1; // ask the caller to free the memory allocated
// for a1
}
since this function is writen explicit the compiler will
invoke this function and not call the default template
function.
this is what appears to me. haven't coded and verified.
// Regards, SADIQ
| Is This Answer Correct ? | 4 Yes | 4 No |
Answer / pranay
MISTAKE:
1.returning a temp object so it goes out of scope.
2.using + for c-type strings.
SOLUTION:
string s = Add("SAM","SUNG");
| Is This Answer Correct ? | 1 Yes | 1 No |
Answer / mms zubeir
There are two things to be considered here.
First, T will be an unknown type in the place where we call
which gives a compilation error.
Second, if we call like this:
std::string c = Add("SAM", "SUNG"); or,
char* c = Add("SAM", "SUNG");
the compiler will convey an error since the arguments to
Add are interpretted as char pointers. The error may be
something like, "cannot add two pointers....".
| Is This Answer Correct ? | 4 Yes | 5 No |
Answer / sv
1) Compiler will throw the error as C++ doesnt support +
operator for string. Another point is T c = Add
("SAM","SUNG"), where the function call assign to a
TEMPLATE object type, it syntactical error.
2)We need to write a seperate add function as given below
char* Add( const char *s1, const char*s2);
This will solve the problem
| Is This Answer Correct ? | 3 Yes | 8 No |
What is an iterator class in c++?
What are the benefits of pointers?
Explain how to initialize a const member data.
Write about c++ storage classes?
how is returning structurs from functions?Show an eg?
Write a function which takes a character array as input and reverses it in place.
2 Answers Lehman Brothers, Vision Infotech,
Define a pdb file.
Is c++ still in demand?
What do you mean by vtable and vptr in c++?
Which function cannot be overloaded c++?
When do you call copy constructors?
What is runtime errors c++?
STL 
