return Statement in C++

In C++, the return statement returns the flow of the execution to the function from where it is called. This statement does not mandatorily need any conditional statements. As soon as the statement is executed, the flow of the program stops immediately and returns the control from where it was called. The return statement may or may not return anything for a void function, but for a non-void function, a return value must be returned. 

Let’s take a look at an example:

12

Explanation: In this example, in add() function, the return a + b returns the sum to the calling function and terminate the execution of the function. In the main function, return 0 indicates that the program executed successfully.

Syntax:

return expression[];

There are various ways to use return statements. A few are mentioned below:

1. Methods not returning a value

In C++ one cannot skip the return statement when the methods are of the return type. The return statement can be skipped only for void types.

a. Not using a return statement in void return type function

When a function does not return anything, the void return type is used. So if there is a void return type in the function definition, then there will be no return statement inside that function (generally).

Example:

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b. Using the return statement in void return type function

Now the question arises, what if there is a return statement inside a void return type function? Since we know that, if there is a void return type in the function definition, then there will be no return statement inside that function. But if there is a return statement inside it, then also there will be no problem if the syntax of it will be: 

This syntax is used in function just as a jump statement in order to break the flow of the function and jump out of it. One can think of it as an alternative to "break statement" to use in functions.

Example:

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But if the return statement tries to return a value in a void return type function, that will lead to errors. 

Incorrect Syntax:

void func() {
return value;
}

Example:

Output:

warning: 'return' with a value, in function returning void

2. Methods returning a value:

For methods that define a return type, the return statement must be immediately followed by the return value of that specified return type. 

Syntax:

return-type func() {
return value;
}

Example:

The sum is 20

Note: We can only return a single value from a function using return statement. To return multiple values, we can use pointers, structures, classes, etc. To know more, click here.