how to run a command only after a certain number of players enter the command

So basically I'm trying to code a plugin that changes a persons prefix to king only after 5 people run the command /king, I got most of it done but I cant figure out how to make it so 5 people have to enter the command before it runs, any ideas?

 

I think I know how to do what you want to do, but first let me confirm: are you trying to make a command where 5 people have to "nominate" a person to be king?

 

Add HashMaps with player names and times they have been nominated, and once the command has been run the 5th time, add the prefix.

 

how do you make hashmap of how many times that player has been nominated?

Nvm, I used my friend google and found out, thank you for putting me on the right track though.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.