Largest Multiple of Three LeetCode solution in JavaScript

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/**
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 * @param {number[]} digits
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 * @return {string}
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 */
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var largestMultipleOfThree = function (digits) {
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  // highest digit first
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  digits.sort((l, r) => r - l);
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  // what is the remainder of the total sum?
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  const sumRemainder = digits.reduce((a, c) => a + c, 0) % 3;
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  if (sumRemainder) {
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    let targetIndex = 0,
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      i = digits.length - 1;
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    // try to find what is the smallest number that can be removed
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    for (; i >= 0; i--) {
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      if ((digits[i] - sumRemainder) % 3 === 0) {
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        targetIndex = i;
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        break;
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      }
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    }
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    if (i < 0) {
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      // iterated the whole loop, couldn't find a single number to remove
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      // remove everything but multiples of 3
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      digits = digits.filter((v) => v % 3 === 0);
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    } else {
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      digits.splice(targetIndex, 1);
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    }
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  }
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  return digits[0] === 0 ? "0" : digits.join("");
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};