C Programming Tutorial

Computer Tutorial

Introduction & History of C Constants & there Types Variables & there Types C Keywords Data Type in C C - Operators First Program in C

Decision Control Statements The if statement Multiple if statement The if-else statement Ternary operator ( ? ) goto statement switch statement

Loops in C The While loop The do-while loop The for loop Nesting of Loops Break & Continue Statement

Array in C Declaration of an Array Entering Data into an Array Reading Data from an Array Array Elements in Memory Passing Array Elements to a Function Passing an Entire Array to a Function Two-Dimensional Arrays Initialising a 2-D Array Reading Data from 2-D Array Memory Map of 2-D Array Three-Dimensional Array

Pointer in C Pointer Variables Declaration Pointer Operators

String in C Pointers and Strings String Functions strlen( ) Function strcpy( ) Function strcat( ) Function strcmp( ) Function

» Function in C » Function Prototypes declaration » Call by Value » Call by Reference » Returning Values » Recursion

Structure in C Declaring a Structure Accessing Structure Members Structure Assignments Arrays of Structures Passing Structures to Functions Structure Pointers Uses of Structures

Union in C Difference Between Structure and Union

File Handling in C File Operations Opening a File Reading from a File Trouble in Opening a File Closing the File Writing to a File File Opening Modes File Handling Functions

Additional Tutorials on C

Objective Question on C

Returning Values

All functions, except those of type void, return a value. This value is specified by the return statement. If a non-void function executes a return statement that does not include a value, then a garbage value is returned.

A Program to demonstrate returning values in function

\* C Program to demonstrate returning values in function *\
# include < stdio.h >
int mul ( int a, int b) ;
int main( )
{

int x, y, z ;
x = 10 ;
y = 20 ;
z = mul ( x , y ) ;
printf(" %d ", mul ( x, y )) ;
mul ( x , y ) ;
return ( 0 ) ;

}
int mul ( int a, int b)
{

return ( a * b ) ;

}

The return statement serves two purposes :

1. On executing the return statement it immediately transfers the control back to the calling program.
2. It returns the value present in the parentheses after return, to the calling program. The value of function is being returned.
» There is no restriction on the number of return statements that may be present in a function. Also, the return statement need not always be present at the end of the called function.
» Whenever the control returns from a function some value is definitely returned. If a meaningful value is returned then it should be accepted in the calling program by equating the called function to some variable.
» If we want that a called function should not return any value, in that case, we must mention so by using the keyword void.
» A function can return only one value at a time.
All the following are valid return statements :
return ( a ) ;
return ( 23 ) ;
return ( 12.34 ) ;
return ;
In the last statement a garbage value is returned to the calling function since we are not returning any specific value.

C Programming Tutorial

Returning Values