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return Statement (C++)

 

The latest version of this topic can be found at return Statement (C++).

Terminates the execution of a function and returns control to the calling function (or to the operating system if you transfer control from the main function). Execution resumes in the calling function at the point immediately following the call.

Syntax

return [expression];  

Remarks

The expression clause, if present, is converted to the type specified in the function declaration, as if an initialization were being performed. Conversion from the type of the expression to the return type of the function can create temporary objects. For more information about how and when temporaries are created, see Temporary Objects.

The value of the expression clause is returned to the calling function. If the expression is omitted, the return value of the function is undefined. Constructors and destructors, and functions of type void,cannot specify an expression in the return statement. Functions of all other types must specify an expression in the return statement.

When the flow of control exits the block enclosing the function definition, the result is the same as it would be if a return statement without an expression had been executed. This is invalid for functions that are declared as returning a value.

A function can have any number of return statements.

The following example uses an expression with a return statement to obtain the largest of two integers.

Example

// return_statement2.cpp  
#include <stdio.h>  
  
int max ( int a, int b )  
{  
   return ( a > b ? a : b );  
}  
  
int main()  
{  
    int nOne = 5;  
    int nTwo = 7;  
  
    printf_s("\n%d is bigger\n", max( nOne, nTwo ));  
}  

See Also

Jump Statements
Keywords