const
  n1 = 4;
  a1:array[1..n1] of string = ('dos','linux','windows','macos');
var
  i,l,il,tl:integer;

  aFIO:array[1..3] of string;
  sFIO:string;
begin
  l:=length( a1[1] );
  il:=1;
  for i:= 2 to n1 do
  begin
    tl := length( a1[i] );
    if l < tl then
    begin
      il := i;
      l := tl;
    end;
  end;
  writeln(a1[il]);

  sFIO := 'Иванов Сергей Петрович';
  l:=length(sFIO);
  il:=1;
  for i:=1 to l do
    if sFIO[i] <> ' ' then
      aFIO[il] := aFIO[il] + sFIO[i]
    else
      il := il + 1;

  writeln(aFIO[1], ' ', aFIO[2][1], '. ', aFIO[3][1], '.');
end.