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 fn_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 the function as follows:
main()
{float a=5, b=15, result;
result=findaverage(a,b);
printf("average=%f\n",result);
}
Note: The return statement passes the result back to the main program.