- #1
AllenHe
- 74
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Can anyone explain to me how are the parameter passed on to the function in C++?
void f(int x) { ... }
// ...
f(3);
// ...
Passing parameters to a function allows for the input of data values that can be used within the function's code. This allows for the function to perform different actions depending on the data values provided.
In C++, parameters can be passed to a function by value, by reference, or by pointer. By value means that a copy of the parameter's value is passed to the function. By reference means that the function has access to the original parameter's value. By pointer means that the function has access to the address of the parameter's value.
In pass by reference, the function has direct access to the original parameter's value and can modify it. In pass by pointer, the function has access to the address of the parameter's value and can modify it indirectly by dereferencing the pointer. Additionally, pass by pointer allows for passing of null values, whereas pass by reference does not.
In C++, default parameters can be specified in the function declaration. This means that if no value is passed for a particular parameter, the default value will be used. Default parameters must be specified at the end of the parameter list and any parameters after the default parameter must also have default values.
No, C++ functions can only return a single value. However, multiple values can be returned by using pass by reference or pass by pointer for some of the parameters. This allows for the function to modify the values of these parameters, which can then be used in the calling code.