#include <windows.h>
#include <string>
using namespace std;
 
extern "C" __declspec(dllexport) int __stdcall sum(int a, int b)
{
	return a+b;
}
 
extern "C" __declspec(dllexport) int __stdcall sub(int a, int b)
{
	return a-b;
}
 
extern "C" __declspec(dllexport) int __stdcall strlen2(LPSTR c)
{
	string s(c);
	return s.size();
} 

library DelphiDLL;
{$APPTYPE CONSOLE}
 
function sum(a,b : integer) : integer; stdcall;
begin
  Result := a + b;
end;
 
function sub(a,b : integer) : integer; stdcall;
begin
  Result := a-b;
end;
 
function strlen2(ins : PChar) : integer; stdcall;
var
  s : string;
begin
  s := ins;
  Result := length(s);
end;
 
exports
  sum,
  sub,
  strlen2;
end.
 

 
namespace sol
{
    class Program
    {
        [DllImport(@"a.dll", EntryPoint = "sum", CallingConvention = CallingConvention.StdCall)]
        private static extern int sum(int a, int b);
 
        static void Main(string[] args)
        {
            int a = 123;
            int b = 321;
            int res = sum(a, b);
        }
    }
}
 

 function sum(a,b:integer);stdcall;cdecl; external 'a.dll'; 

function LoadLibraryEx(LibName: PChar; hFile: Longint; Flags: Longint): Longint; stdcall;
  external 'kernel32.dll' name 'LoadLibraryExA';