const weight = (s: string): number => s.split('').reduce((acc, cur) => acc + parseInt(cur), 0);

const sortWeightInfo = <T extends WeightInfo | DiffInfo>(a: T, b: T): number => {
  if (a[0] !== b[0]) {
    return a[0] - b[0];
  } else if (a[1] !== b[1]) {
    return a[1] - b[1];
  } else {
    return a[2] - b[2];
  }
}

type WeightInfo = [
  number, // weight
  number, // index
  number  // number
];
type DiffInfo = [
  number, // weight difference
  number, // weight sum
  number, // index sum
  number, // index of first number
  number  // index of second number
];

export function closest(strng: string): number[][] {
  if (strng === '') return [];

  const weights: WeightInfo[] = strng
    .split(' ')
    .map((s, i) => [weight(s), i, parseInt(s)]);

  // calculate all weight differences, weight sum, and index sum
  const diffs: DiffInfo[] = [];
  for (const [weight, index, num] of weights) {
    for (let i = index + 1; i < weights.length; i++) {
      if(i >= weights.length) break;

      const [weight2, index2, num2] = weights[i];
      const weightDiff = Math.abs(weight - weight2);
      const weightSum = weight + weight2;
      const indexSum = index + index2;
      diffs.push([weightDiff, weightSum, indexSum, index, index2]);
    }
  }

  // sort by weight difference, weight sum, and index sum
  diffs.sort(sortWeightInfo);

  const minimumDiff = diffs[0]
  const firstNumIndex = minimumDiff[3];
  const secondNumIndex = minimumDiff[4];

  const result = [
    weights[firstNumIndex],
    weights[secondNumIndex]
  ].sort(sortWeightInfo)

  return result;
}