Routing is not working for Symfony version 2.5

[hitendraraj]

app/config/routing.yml

_imagine:
resource: .
type: imagine

Fatal error: Uncaught exception 'Symfony\Component\Config\Exception\FileLoaderLoadException' with message 'Cannot load resource ".".' in D:\wamp\www\sasnew\vendor\symfony\symfony\src\Symfony\Component\Config\Loader\Loader.php on line 77
( ! ) Symfony\Component\Config\Exception\FileLoaderLoadException: Cannot load resource ".". in D:\wamp\www\sasnew\vendor\symfony\symfony\src\Symfony\Component\Config\Loader\Loader.php on line 77