Amazon OA - Feb 2025

Full OA was 2 coding questions + some GDS questions + some behavioural/culture fit questions. (MCQ)

Amazon L5, Feb 2025

Don't really remember Q1, but it was a pretty straightforward question

Here's Q2: Given two strings s and t, return the number of subsequences of s that are lexicographically strictly greater than t, modulo 1e9 + 7.

Example s = "aba" t = "ab" => expected return: 3

 Subsequence of s   |   strictly greater than t?
-------------------------------------------------
    a               |       no
    ab              |       no
    aa              |       no
    aba             |       yes
    b               |       yes
    ba              |       yes
    a               |       no

I came up with a DFS+Memo approach, that keeps track of the index of s and the length of the current subsequence I am pathing, so typically kinda a 2D top down DP, but only passed like 11 or 12 test cases out of 15 (TLE) :( ‎ Anyways, still got an invite for next steps the following day. Good luck!