编辑代码

let numArray = [2, 3, 5, 10, 6, 8, 3, 1, 9, 12, 15, 4];
let nums = numArray.concat();

function findStander(arr, low, high) {
    if (low < high) {
        let base = arr[low];
        let l = low;
        let h = high;
        while (l < h) {
            while (l < h && arr[h] >= base) {
                h--;
            }
            arr[l] = arr[h];
            while (l < h && arr[l] <= base) {
                l++;
            }
            arr[h] = arr[l];
        }
        arr[l] = base;
        return l;
    }
}
// 这是不是纯函数方法，改变了原有数组
function quickSort(arr, low = 0, high = arr.length - 1) {
    if (low >= high) return
    var stand = findStander(arr, low, high);
    console.log(`arr: ${arr}， stand: ${stand}`);
    quickSort(arr, low, stand - 1);
    quickSort(arr, stand + 1, high);
}

quickSort(nums)
console.log(nums)