Armory Software Engineer interview questions

Awful, they sent me a technical assessment that took me 8 hours to figure out. My solution was optimal. Their problem was a k-way merge. I was told that they had not seen a solution as efficient as mine. It was terrible because on the first interview we agreed to a salary amount, this was before taking the assessment. After getting an offer they low-balled me with 40% less than we had INITIALLY AGREED. I had only completed the technical assessment based on this initial conversation, I was effectively tricked into completing their test. I believe they low-balled me because they thought that they could take advantage because I live outside the US, as they explicitly tried to sell the low-ball offer to me by bringing up my location of residence. Initially we had agreed to 115k annual salary, at the end they offered under 80k.