归并排序的基本原理是，先将一个数组递归地二分，然后在分到一定程度之后将它们重新组合，并且在组合的过程中按顺序排列，达到排序的目的。

 

import java.util.*fun merge(a:Array
     
      , low:Int, mid:Int, high:Int){    var temp = IntArray(high-low+1)    var i:Int = low    var j:Int = mid + 1    var k:Int = 0 　　//合并过程    while( i<= mid && j<= high){        temp[k++] = if(a[i]< a[j]) a[i++] else a[j++]    }    while(i<= mid) temp[k++] = a[i++]    while(j<= high) temp[k++] = a[j++]    for(k2 in temp.indices) a[k2+ low] = temp[k2]}fun mergeSort(a:Array
      
       , low:Int, high:Int){    var mid:Int = (low+ high)/ 2    if( low< high){        mergeSort(a, low, mid)        mergeSort(a, mid+1, high)        merge(a, low, mid, high)    }}fun main(args:Array
       
        ){    var a = arrayOf(37, 26, 12, 8, 63, 5, 9, 57, 60)    mergeSort(a, 0, a.size-1)    println("结果：${Arrays.toString(a)}")}