Decode String

Stacks

medium

Question(s)

Given an input string such as 'a2b3c4' produce an output string like 'aaabbbbccccc' Also seen as: Given an encoded string, return its decoded string. The encoding rule is: k[encoded_string], where the encoded_string inside the square brackets is being repeated exactly k times. Note that k is guaranteed to be a positive integer. You may assume that the input string is always valid; there are no extra white spaces, square brackets are well-formed, etc. Furthermore, you may assume that the original data does not contain any digits and that digits are only for those repeat numbers, k. For example, there will not be input like 3a or 2[4].

Ready to practice with a mock interview?

Book mock interviews with engineers from Google, Facebook, Amazon, or other top companies. Get detailed feedback on exactly what you need to work on. Everything is fully anonymous.

Computer Dude