Algorithms - Find the Symmetric Difference

Tell us what’s happening:
Describe your issue in detail here.

  **Your code so far**
function sym(args) {
return args;
}

sym([1, 2, 3], [5, 2, 1, 4]);
  **Your browser information:**

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.0.0 Safari/537.36

Challenge: Algorithms - Find the Symmetric Difference

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