17 Letter Combinations of a Phone Number

Code and explanation: https://www.patreon.com/posts/letter-... Given a string containing digits from 2-9 inclusive, return all possible letter combinations that the number could represent. Return the answer in any order. A mapping of digits to letters (just like on the telephone buttons) is given below. Note that 1 does not map to any letters. Example 1: Input: digits = "23" Output: ["ad","ae","af","bd","be","bf","cd","ce","cf"] Example 2: Input: digits = "" Output: [] Problem Statement link: https://leetcode.com/problems/letter-... ------------------------------------------------------------------------------------------ Here are some of the gears that I use almost everyday: 🖊️ : My Pen (Used in videos too): https://amzn.to/38fKSM1 👨🏻‍💻 : My Apple Macbook pro: https://amzn.to/3w8iZh6 💻 : My gaming laptop: https://amzn.to/3yjcn23 📱 : My Ipad: https://amzn.to/39yEMGS ✏️ : My Apple Pencil: https://amzn.to/3kMnKYf 🎧 : My Headphones: https://amzn.to/3kMOzM7 💺 : My Chair: https://amzn.to/385weqR 🛋 : My Table: https://amzn.to/3TyU2IU ⏰ : My Clock: https://amzn.to/3slFUV3 🙋🏻‍♀️ : My girlfriend: https://amzn.to/3M6zLDK ¯\_(ツ)_/¯ PS: While having good gears help you perform efficiently, don’t get under the impression that they will make you successful without any hard work.