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下面是我做的一个DLL，build有问题：
[Error] dllcomserver.dpr(10): Undeclared identifier: 'Interger'
[Error] dllcomserver.dpr(23): Declaration of 'max' differs from previous declaration
[Warning] dllcomserver.dpr(25): Comparing signed and unsigned types - widened both operands
[Error] dllcomserver.dpr(31): Declaration of 'mix' differs from previous declaration
[Warning] dllcomserver.dpr(33): Comparing signed and unsigned types - widened both operands//文件中的代码
library dllcomserver;uses
  SysUtils,
  Classes;type
  TComp=Class
  public
    function max(x,y:Interger):Integer;virtual;abstract;
    function mix(x,y:Interger):Integer;virtual;abstract;
  end;type
  TCompImpl=Class(TComp)
  public
    function max(x,y:Interger):Integer;override;
    function mix(x,y:Interger):Integer;override;
  end;{TCompImpl}function TCompImpl.max(x,y:Integer):Integer;
begin
  if x>y then
    result:=x
  else
    result:=y;
end;function TCompImpl.mix(x,y:Integer):Integer;
begin
  if x<y then
    result:=x
  else
    result:=y;
end;function CreateCompImpl:TCompImpl;stdcall;
begin
  result:=TCompImpl.Create;
end;function add(x,y:Interger):Interger;stdcall;
begin
  result:=x+y;
end;function multi(x,y:Interger):Interger;stdcall;
begin
  result:=x*y;
end;exports
  add,multi,CreateCompImpl;
begin
end.