var
  arRnd, arOdd, arEven: array of integer;
const
  maxValue = 50; // Max value of rnd
  maxLen = 30; // arRnd.Length
begin
  SetLength(arRnd, maxLen);
  SetLength(arOdd, maxLen);
  SetLength(arEven, maxLen);
// Init
  for var i := Low(arRnd) to High(arRnd) do
    arRnd[i] := random(MaxValue + 1);

  write('len=', arRnd.Length,' ', arRnd);
  writeln();

// separate odd and even   
  var j: integer = 0;
  var k: integer = j;
  for var i := Low(arRnd) to High(arRnd) do
    case Odd(arRnd[i]) of
      True: begin
              arOdd[j] := arRnd[i];
              Inc(j);
            end;
      False: begin
               arEven[k] := arRnd[i];
               Inc(k);
             end;
    end;
      
// truncate
  SetLength(arOdd, j);  
  SetLength(arEven, k);

// sort up
  arOdd.Sort;
// reverse
  Reverse(arOdd);
// sort up
  arEven.Sort;

// splice  
  for var i := Low(arOdd) to High(arOdd) do
    arRnd[i] := arOdd[i];
  for var i := Low(arEven) to High(arEven) do
    arRnd[arOdd.Length + i] := arEven[i];
// out 
  write('j=',j,'   ',arOdd);
  writeln();
  write('k=',k,'   ', arEven);
  writeln();
  write('j+k=',j+k,' ', arRnd);
  
end.