生成所有排列数，包括数组中的.5和.25的小数

function generatePermutations(arr) {
  arr.sort(); // 排序确保小数位在数组的最后
  const result = [];
  
  function generateHelper(currPermutation, pos, arr, result) {
    if (pos === arr.length) {
      result.push(currPermutation.slice()); // 将当前排列数添加到结果集中
    } else {
      for (let i = pos; i < arr.length; i++) {
        currPermutation.push(arr[i]);
        generateHelper(currPermutation, pos + 1, arr, result);
        currPermutation.pop();
      }
    }
  }
  
  generateHelper([], 0, arr, result);
  return result;
}

const array = [1, 2, 3, 4, 0.5, 0.25];
const permutations = generatePermutations(array);
console.log(permutations);