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Leetcode 17. Letter Combinations of a Phone Number

Given a string of digits 2–9, return all possible letter strings by mapping each digit to its phone-keypad letters — effectively computing the Cartesian product of per-digit letter sets; this is typically solved by DFS/backtracking to enumerate combinations (digits length ≤ 4).

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Company

Level

Region

Mid October, 2025

LinkedIn

Mid-level

Early October, 2025

LinkedIn

Mid-level

Early September, 2025

LinkedIn

Mid-level

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