A walkthrough of a recursive algorithm problem.

The Problem:

Given an object oldObj, write a function flattenObject that returns a flattened version of it. If a certain key is empty, it should be excluded from the output. When you concatenate keys, make sure to add the dot character between them. For instance when flattening KeyB, c and d the result key would be KeyB.c and KeyB.d. Example: const oldObject = {
"KeyA": 1,
"c": 2,
"d": 3,
"f": 7,
"" : 2
"KeyA": 1,
"KeyB.c": 2,
"KeyB.d": 3,
"KeyB.e.f": 7,
"KeyB.e": 2

The first…

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Ann-Marie Kemp is a full stack software engineer living in New York City. She is currently studying algorithms and job hunting for a junior developer position.

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