program tenbytes { www.merlyn.demon.co.uk  >= 2002-02-18 } ;

type A5 = array [1..5] of word ;
const Q : extended = 1.0/65536.0 ;

function TwoTo(const P : integer) : extended ;
var S : extended ; J : integer ;
begin S := 1 ;
  for J := 1 to Abs(P) do S := 2.0*S ; { but see ... }
  if P<0 then S := 1.0/S ;
  TwoTo := S end {TwoTo} ;

function TenToExt(const Ten : extended) : extended ;
var S : extended ; A : A5 absolute Ten ;
begin
  S := 2.0 *  (((A[1]*Q+A[2])*Q+A[3])*Q+A[4])*Q ;
  if A[5]>32767 then S := -S ;
  TenToExt := S * TwoTo(integer(A[5] and $7FFF)-16383) end {TenToExt} ;

Var J : integer ; Z : extended ;

BEGIN ;
Randomize ;
for J := 1 to 10 do begin Z := Random*123456789 ;
  Writeln(Z:24:10, TenToExt(Z):24:10, TenToExt(-Z):24:10) ;
  end ;
Z := 0 ; Writeln(Z:24:10, TenToExt(Z):24:10) ;
Readln ;
END.  Slightly tested.  Ignores NaN & Inf.