𝗗𝗮𝘆 𝟮𝟳/𝟭𝟬𝟬 | 𝗗𝗲𝗰𝗼𝗱𝗲 𝗦𝘁𝗿𝗶𝗻𝗴 Day 27 ✅ — When recursion makes everything elegant. 𝗧𝗼𝗱𝗮𝘆'𝘀 𝗣𝗿𝗼𝗯𝗹𝗲𝗺: ✅ 𝗣𝗿𝗼𝗯𝗹𝗲𝗺 #𝟯𝟵𝟰: Decode String (Medium) 𝗪𝗵𝗮𝘁 𝗖𝗹𝗶𝗰𝗸𝗲𝗱: Decode strings like "3[a2[c]]" → "accaccacc". Numbers indicate repetition, brackets show nested patterns. My first thought? Stack. But then I realized: nested brackets = 𝗿𝗲𝗰𝘂𝗿𝘀𝗶𝗼𝗻 territory. Each time I hit '[', recursively decode what's inside. When I hit ']', return to the outer level. The recursion naturally handles the nesting. 𝗠𝘆 𝗔𝗽𝗽𝗿𝗼𝗮𝗰𝗵: 👉 Build number from consecutive digits 👉 When '[' appears, recursively decode inner string 👉 Repeat the decoded string by the number 👉 When ']' appears, return result to caller 👉 Regular characters get appended directly Time: O(maxK × n) where maxK is max repeat count, Space: O(n) for recursion stack 𝗠𝘆 𝗥𝗲𝗮𝗹𝗶𝘇𝗮𝘁𝗶𝗼𝗻: Recursion isn't just for trees and graphs—it's for any problem with 𝗻𝗲𝘀𝘁𝗲𝗱 𝘀𝘁𝗿𝘂𝗰𝘁𝘂𝗿𝗲𝘀. The key: recognize when a subproblem looks exactly like the main problem. That's your recursion signal. 27 days in, and I'm getting more comfortable with recursive thinking. 𝗖𝗼𝗱𝗲: https://lnkd.in/gFfUH6bk 𝟮𝟳 𝗱𝗮𝘆𝘀 𝘀𝘁𝗿𝗮𝗶𝗴𝗵𝘁. 𝗔𝗹𝗺𝗼𝘀𝘁 𝗮 𝗺𝗼𝗻𝘁𝗵. Every problem teaches a pattern. Every pattern becomes a tool. 𝗗𝗮𝘆 𝟮𝟳/𝟭𝟬𝟬 ✅ | 𝟳𝟯 𝗺𝗼𝗿𝗲 𝘁𝗼 𝗴𝗼! #100DaysOfCode #LeetCode #Recursion #StringManipulation #DataStructures #CodingInterview #TechnicalInterview #SoftwareEngineer #FAANG #ProblemSolving #Algorithms #Java #Programming #ComputerScience #DeveloperJourney #LearnInPublic #SoftwareDevelopment #CodingSkills #TechJobs #CareerGrowth

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