Answer / roshanpr

During pass by value a duplicate copy of the parameters
passed are created. Any changes made to copy will not
reflect the actual parameters.

In pass by pointer(it called as pass by address) duplicate
copy is not created. and any chagnes made to copy will
reflect in actual parameters also.

Answer / ven

Pass by value - a copy is made

Pass by pointer ( explicit pointer)
example:
void func(int * ptr_sent)
main()
{
int i;
int *p;
p = &i;
func(p);
}

void func(int * ptr_sent)
{
*ptr_sent = *ptr_sent + 2
// adds 2 to the value in location pointed by ptr_sent
}

Pass by reference (implicit pointer)
example:
void func(int &ref_sent)
main()
{
int i;
func(&i);
}

void func(int &ref_sent)
{
ref_sent = ref_sent + 2
// adds 2 to the ref_sent
// Please note that you do not need * when using reference
// Any code manipulating reference reflects changes on i
}

Answer / ranjeet garodia

Pass by value - a copy is made

Pass by pointer ( explicit pointer)
example:
void func(int * ptr_sent)
main()
{
int i;
int *p;
p = &i;
func(p);
}

void func(int * ptr_sent)
{
*ptr_sent = *ptr_sent + 2
// adds 2 to the value in location pointed by ptr_sent
}

answers given by yen .. there is one error ... in pass by
reference .. when calling function pass the variable not
the address....fun(i) should be called instead of fun(&i)

Pass by reference (implicit pointer)
example:
void func(int &ref_sent)
main()
{
int i;
func(i); // call by reference
}

void func(int &ref_sent)
{
ref_sent = ref_sent + 2
// adds 2 to the ref_sent
// Please note that you do not need * when using reference
// Any code manipulating reference reflects changes on i
}

Answer / sampurna pandey

i am not agree with Ranjeet, you mention this

main()
{
int i;
func(i); // call by reference
}

but fun(i) is a call by value not call by reference

your code will give compile error.

Ven eample is right.

Answer / sanish joseph

In Pass by value,copy of the value is passed, but in pass by
reference the address of the variables are passed as a
reference.pointer are variables storing the address of
another variable so it can be used as a pass by referece,
den it s teamed "passing by pointer".

How can I learn c++ easily?

0 Answers  

Explain what happens when a pointer is deleted twice?

0 Answers  

What is the Difference between "vector" and "array"?

15 Answers   Covansys, Gambit, TCS, Wipro,

What is switch case in c++ syntax?

0 Answers  

What is object slicing and how can we prevent it?

2 Answers   Tech Mahindra,

How do you traverse a btree in backward in-order?

0 Answers  

What is the need of a destructor? Explain with the help of an example.

0 Answers  

Why do you use the namespace feature?

0 Answers  

Can union be self referenced?

0 Answers  

Why did you leave your last job?

2 Answers  

What type of question are asked in GE code writing test based on c++ data structures and pointers?

0 Answers  

What is a namespace in c++?

3 Answers