Var
  n : longint ;
  a,x : array[0..500000] of longint ;

Procedure Enter ;
    var i,j : longint ;
    begin
        read(n) ;
        for i := 1 to n do read(x[i]) ;
    end ;

Procedure Main ;
    var i,j,cnt,len : longint ; ok  :   boolean ;
    begin
        cnt := 0 ;
        for i := 2 to n do a[i-1] := x[i] - x[i-1] ;
        for len := 1 to n-1 do
            begin
                ok := false ;
                for i := len+1 to n-1 do
                    if ((i mod len <> 0) and (a[i mod len] <> a[i])) or ((i mod len = 0) and (a[len] <> a[i])) then begin ok := true ; break ;  end ;
                if (ok) then continue ;
                writeln(len) ;
                for i := 1 to len do writeln(a[i]) ;
                exit ;
            end ;
    end ;

Begin
    ASSIGN(input,'reguli.in') ; reset(input) ;
    ASSIGN(output,'reguli.out') ; rewrite(output) ;
    enter ;
    Main ;
    CLOSE(input) ; CLOSE(output) ;
End.