This was for Salesforce, Bellevue WA.

The question was HackerRank "Austin 1", it was related to Math. Initially I spent more time on reading the question which was too lengthy, and later I under estimated the formula by taking only examples visible in the question, when I realized my formula was wrong I had very less time to change it, was able to solve few test cases.

I recommend people to read the question and then if it is crazy math I feel it's okay to lookup those formulas online, I don;t know why Salesforce is screening people based on Math. Very Bad Experience.