var
s:string;
i:integer;
begin
readln(s);
i:=1;
repeat
insert(s[i],s,i);
inc(i,2)
until
i>length(s);
writeln(s)
end.
var
s:string;
i:integer;
begin
readln(s);
i:=1;
repeat
insert(s[i],s,i);
inc(i,2)
until
i>length(s);
writeln(s)
end.