Function and Procedure

There are two kind of subroutine in Pascal : Function and Procedure. The difference between these subroutines is in return value. Function gives a return value, but procedure doesn’t. The structure of function and procedure are the same :

Here is the example of procedure and function :

program FunctionAndProcedure;
{$APPTYPE CONSOLE}
uses
   SysUtils;

procedure Add1(x, y : integer);
 var
  z : integer;
begin
  z := x + y;
  writeln(x,' + ',y,' = ',z,' (using procedure)');
  readln;
end;

function Add2(x, y : integer) : integer;
begin
  Add2 := x + y;
end;

begin
  Add1(25,10);
  writeln('25 + 40 = ',Add2(25,40),' (using function)');
  readln;
end.

You can download the complete code here.