Use of Subroutines

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Sample program : use of subroutines

So far, we have used only printf function that has been provided by the C system. The program shown in following program uses a user-defined function. A function defined by the user is equivalent to a subroutine in FORTRAN or subprogram in BASIC.

This program presents a very simple program that uses a mul( ) function. The program will print the following output.

Multiplication of 5 and 10 is 50



The mul( ) function multiplies the values of x and y and the result is returned to the main( ) function when it is called in the statement.

         
       c = mul ( a, b ) ;


The mul ( ) has two arguments x and y that are declared as integers. The values of a and b are passed on to x and y respectively when the function mul ( ) is called.

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