You can also pass arrays to a function :
void myFunction(int myNumbers[5]) {
for (int i = 0; i < 5; i++) {
cout << myNumbers[i] << "\n";
}
}
int main() {
int myNumbers[5] = {10, 20, 30, 40, 50};
myFunction(myNumbers);
return 0;
}
In the examples from the previous page, we used normal variables when we passed parameters to a function. You can also pass a reference to the function. This can be useful when you need to change the value of the arguments: Continue reading C++ Functions – Pass By Reference
The void keyword, used in the previous examples, indicates that the function should not return a value. If you want the function to return a value, you can use a data type (such as int, string, etc.) instead of void, and use the return keyword inside the function: Continue reading C++ The Return Keyword
Inside the function, you can add as many parameters as you want:
void myFunction(string fname, int age) {
cout << fname << " Refsnes. " << age << " years old. \n";
}
int main() {
myFunction("Liam", 3);
myFunction("Jenny", 14);
myFunction("Anja", 30);
return 0;
}
// Liam Refsnes. 3 years old.
// Jenny Refsnes. 14 years old.
// Anja Refsnes. 30 years old.
Note that when you are working with multiple parameters, the function call must have the same number of arguments as there are parameters, and the arguments must be passed in the same order.
You can also use a default parameter value, by using the equals sign (=).
If we call the function without an argument, it uses the default value (“Norway”):
void myFunction(string country = "Norway") {
cout << country << "\n";
}
int main() {
myFunction("Sweden");
myFunction("India");
myFunction();
myFunction("USA");
return 0;
}
// Sweden
// India
// Norway
// USA
A parameter with a default value, is often known as an “optional parameter“. From the example above, country is an optional parameter and "Norway" is the default value.
Information can be passed to functions as a parameter. Parameters act as variables inside the function.
Parameters are specified after the function name, inside the parentheses. You can add as many parameters as you want, just separate them with a comma: Continue reading C++ Function Parameters
A function is a block of code which only runs when it is called.
You can pass data, known as parameters, into a function.
Functions are used to perform certain actions, and they are important for reusing code: Define the code once, and use it many times.
You can also change the pointer’s value. But note that this will also change the value of the original variable: Continue reading C++ Modify Pointers
In the example from the previous page, we used the pointer variable to get the memory address of a variable (used together with the & reference operator). However, you can also use the pointer to get the value of the variable, by using the * operator (the dereference operator): Continue reading C++ Dereference
You learned from the previous chapter, that we can get the memory address of a variable by using the & operator:
string food = "Pizza"; // A food variable of type string
cout << food; // Outputs the value of food (Pizza)
cout << &food; // Outputs the memory address of food (0x6dfed4)
A pointer however, is a variable that stores the memory address as its value.
A pointer variable points to a data type (like int or string) of the same type, and is created with the * operator. The address of the variable you’re working with is assigned to the pointer: Continue reading C++ Pointers