Leetcode 792. Number of Matching Subsequences

Count how many strings in words appear as subsequences of a given string s (characters in order but not necessarily contiguous). The challenge is to efficiently test many short patterns (words.length ≤ 5000, each ≤50) against a longer text s (|s| up to 5·10^4) using preprocessing or streaming/multi-pointer techniques to avoid repeated scans.