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Recursion: Fibonacci String

JavaScriptHardrecursionstrings

Instructions

A Fibonacci string is a precedence of the Fibonacci series. It works with any two characters of the English alphabet (as opposed to the numbers 0 and 1 in the Fibonacci series) as the initial items and concatenates them together as it progresses similarly to that of the Fibonacci series. See examples for more details.

Examples

fibStr(3, ["j", "h"]) ➞ "j, h, hj"

fibStr(5, ["e", "a"]) ➞ "e, a, ae, aea, aeaae"

fibStr(6, ["n", "k"]) ➞ "n, k, kn, knk, knkkn, knkknknk"

Notes

  • All values for n will be at least 2.
  • It is expected from the challenge-takers to come up with a solution using the concept of recursion or the so-called recursive approach.
  • You can read more topics about recursion if you aren't familiar with it yet or haven't fully understood the concept behind it before taking up this challenge or unless otherwise.
  • A recursive approach is prone to Uncaught RangeError or exceeding the maximum call size of the stack, deal with it accordingly and appropriately.
  • An iterative version of this challenge can be found via this link.
  • A collection of challenges in recursion can be found via this link.
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