The interview started with a brief introduction from both sides. The coding question followed, then I asked my questions for the interviewer. A huge chunk of the time was spent on the coding question. The interviewer answered my questions in good faith.

Solve a set of equations, represented as lists, such as [["A","B","C"], ["C","1"], ["B","C","1"], ["D","B","1"]]. These equations represent relationships like A = B + C. The first element in each list is always followed by an equals sign, and only the '+' operator is used. The solution should be returned as a dictionary.