var a:array[1..10000]of longint; i,j,n,nn,t:longint;begin read(n); nn:=n; for i:=1 to n do read(a[i]); for i:=1 to n-1 do for j:=i+1 to n do begin if a[i]>a[j] then begin t:=a[i]; a[i]:=a[j]; a[j]:=t; end; if a[i]=a[j] then begin dec(nn); a[i]:=0; end; end; writeln(nn); for i:=1 to n do if a[i]<>0 then write(a[i],' ');end.
