What is the difference between Call by value and Call by reference?

What is the difference between Call by value and Call by reference?
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1 Answer

Answer :

A: Call By Value : When a function is called by value, then the value of the actual parameter is copied to the formal parameter (i.e. a separate copy is made). Any changes made with the values of the formal parameter does not affect (change) the actual parameter.

Call By Reference : When a function is called by reference, then the reference(address) of the actual parameter is sent to the formal parameter. Any changes made with the values at that address of the formal parameter affects (changes) the value of the actual parameter.
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