Concatenating Strings Mock Interview (Senior MAANG Engineer) | Summary and Q&A

TL;DR

Given a string and an integer K, remove K adjacent equal letters from the string and concatenate the remaining parts.

Key Insights

• 🧩 The problem requires removing adjacent letters in a string based on a given integer K and concatenating the remaining parts.
• 🔍 The solution involves iterating through the string, comparing characters and keeping count using a stack.
• 📝 The order of removal doesn't matter, so the solution is efficient regardless of the value of K.
• 🧮 The worst-case time complexity of the brute force solution is O(n^2) but can be improved.
• 💡 An optimized solution involves using a stack to store characters and their counts, allowing for efficient removal and concatenation.
• 👍 It's important to have a clear understanding of the problem and ask for clarifications and examples if needed.
• 🗂️ Code readability can be improved by using lists to store character-count pairs in the stack.
• ⚙️ The final implementation should have a time complexity of O(n) and handle both positive and negative test cases efficiently.

Transcript

you are given a string let's call it s and you're giving them an integer let's call that K this integer K we'll call it the duplicate removal integer and it's a variable that basically tells us how many adjacent equal letters we want to remove from s and then concatenate the two sides of this string that are on either side of the of the part of the... Read More