Program String66;
Var
inString : String;
s, temp : String;
i : Integer;
Begin
ReadLn(inString);
Repeat
Inc(i);
temp := temp + inString[i];
If i = Length(inString) Then Break;
Inc(i);
s := s + inString[i];
If i = Length(inString) Then Break;
Until False;
InString := temp;
For i := 1 To Length(temp) Do
inString[Length(temp)-i + 1] := temp[i];
inString := s + inString;
WriteLn(inString);
End.