Petrol pumps know when to turn themselves off

Sorry about that. I am using a mobile phone to access internet and it is a pain both to type and copy-paste text. Some part of the title was left out by mistake while copying. And the title edit box of HN post is not wide enough on the mobile screen so I did not realise the mistake. And now I am not able to edit the title of the post.

I will delete the post and repost it using the correct title.