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 the two groups merged into an orderly array, the array each time the scale of the merger. Will be doubled, and ultimately will be the original array into a disorderly orderly array.