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Find the Symmetric Difference

What is Symmetic Difference?

Symmetric difference is a concept in set theory and mathematics that describes the set of elements that are in either of two sets but not in both. In other words, given two sets A and B, the symmetric difference of A and B (△ or ⊕) contains all elements that are in A or in B, but not in both A and B simultaneously.

Let's delve into a JavaScript function that computes the symmetric difference of multiple arrays:

javascript
function symmetricDifference(...args) { const result = new Set(args[0]); for (let i = 1; i < args.length; i++) { let currentSet = new Set(args[i]); for (const value of currentSet) { if (result.has(value)) { result.delete(value); } else { result.add(value); } } } return Array.from(result); }

Context

  1. The function symmetricDifference accepts a variable number of arrays using the rest parameter syntax (...arrays), allowing flexibility in the number of sets provided as input.

  2. It initializes a Set named result with the elements of the first array arrays[0]. Using a Set ensures uniqueness and automatically removes any duplicates.

  3. It iterates through the remaining arrays, converting each array into a Set and comparing its elements with those in the result set.

  4. For each value in the current array (currentSet), it checks if it exists in the result set. If it does, the value is removed from result using the delete() method. If not, it is added using the addd() method.

  5. Finally, the function returns the symmetric difference as an array, converting the Set back using Array.from().

Example Usage

javascript
const A = [1, 2, 3]; const B = [2, 4, 5, 1]; const C = [2, 3, 6]; console.log(symmetricDifference(A, B)); //Output: [ 3, 4, 5 ] console.log(symmetricDifference(A, B, C)); //Output: [ 4, 5, 2, 6 ]

Conclusion

With this JavaScript function, you can easily find the differences between sets. It helps you understand how sets relate to each other and solve problems quickly.