如何“取消扁平化”数组或创建成对的数组

function pairwise(arr) {
  const result = [];
  for (let i = 0; i < arr.length; i += 2) {
    result.push([arr[i], arr[i + 1]]);
  }
  return result;
}

const flatArray = [1, 2, 3, 4, 5, 6];
const pairedArray = pairwise(flatArray);
console.log(pairedArray); // 输出: [[1, 2], [3, 4], [5, 6]]

function chunkArray(arr, size) {
  const result = [];
  for (let i = 0; i < arr.length; i += size) {
    result.push(arr.slice(i, i + size));
  }
  return result;
}

const flatArray = [1, 2, 3, 4, 5, 6, 7, 8];
const chunkedArray = chunkArray(flatArray, 3);
console.log(chunkedArray); // 输出: [[1, 2, 3], [4, 5, 6], [7, 8]]

function pairwise(arr) {
  const result = [];
  for (let i = 0; i < arr.length; i += 2) {
    if (i + 1 < arr.length) {
      result.push([arr[i], arr[i + 1]]);
    } else {
      result.push([arr[i]]);
    }
  }
  return result;
}

const flatArray = [1, 2, 3, 4, 5];
const pairedArray = pairwise(flatArray);
console.log(pairedArray); // 输出: [[1, 2], [3, 4], [5]]