There are 4 interns at the new government agency. All 4 are comp sci majors. John is the only male. The three girls are all close but secretly like John. Lisa is playing hard to get and hopes John will make a move but could trick John into asking her out. Anne likes John and flirts openly but repeatedly tells everyone she will not date a smoker. Sarah is the smartest out of the bunch and wants John to prove to her that he can fulfill her intellectual needs.
One day John arrives at his computer and there is a post-it note with a heart around it and the following numbers written in it.
Being that asking any of the girls will dissuade the other two from ever wanting to date him, John must guess who left the message and make a gesture to show he wants to date her.
Who left the message? What does John do?