Javascript Freecodecamp Algorithm #27: Find The Symmetric Difference (N Squared Solution)

symmetric-difference-2.js

const symOfTwo = (arr1, arr2) => {
  const set1 = new Set(arr1);
  const set2 = new Set(arr2);

  const combinedArr = [...set1, ...set2];

  const elObj = {};
  for (const el of combinedArr) {
    if (el in elObj) {
      elObj[el]++;
    } else {
      elObj[el] = 1;
    }
  }

  const output = [];
  for (const el in elObj) {
    if (elObj[el] === 1) {
      output.push(Number(el));
    }
  }

  return output;
};

function sym() {
  const arrOfArrs = [...arguments];
  let output = arrOfArrs[0];
  for (let i=1; i < arrOfArrs.length; i++) {
    output = symOfTwo(output, arrOfArrs[i]);
  }

  return output;
}