var a,b,c:integer;
begin
readln(a,b,c);
if((a=b)or(b=c)or(c=a)) then writeln(':)') else writeln(':(')
end.
var a,b,c:integer;
begin
readln(a,b,c);
if((a=b)or(b=c)or(c=a)) then writeln(':)') else writeln(':(')
end.