首先通过递归调用，将原数组不断的分小，最终将数组分成N份。然后将有序的两组合并成一个有序数组，每合并一次数组的规模.就会翻倍，最终会将原来无序的数组变成一个有序的数组。-First of all, through the recursive calls, the original constant array of small points, which will ultimately be divided into N copies of the array. And then ordered