C provides functions which are again similar most languages. One difference is that C regards main() as function. Also unlike some languages C does not have procedures - it uses functions to service both requirements.
Let us remind ourselves of the form of a function:
returntype function_name (parameterdef1, parameterdef2, ...)
{
localvariables
functioncode
}
Let us look at an example to find the average of two integers:
float findaverage(float a, float b)
{ float average;
average = (a+b)/2.;
return(average)
}
We would call this function in the main program as follows:
main()
{
float d=5;, y=15, result;
reult=findaverage(d,y)
printf("average=%f\n",result);
}
Note: The return statement passes the result back to the main program.