1  2  3  4   
      5   
      6    7  8  9   归并排序是一种分治算法，其思想是将原始数组分割成较小的数组，直到每个小数组只有一个位置，接着将小数组归并成较大数组，知道最后只有一个排序完毕的大数组。10 11 

1 var array=[32,12,45,2,57,1,35,7,9,23,32]; 2  3 function mergeRec(array){ 4    5   var length=array.length; 6   if(length==1) 7     return array; 8   var mid = Math.floor(length/2); 9   var left = array.slice(0,mid);10   var right = array.slice(mid,length);11   12   return mergeSort(mergeRec(left),mergeRec(right));13 }14 15 function mergeSort(left,right){16   var result=[];17   do18   {19     if(left[0]>right[0]){20       result.push(right.shift());21     }22     else{23       result.push(left.shift());24     }25   }26   while(left.length>0&& right.length>0);27   28   return result.concat(left).concat(right);29   30 }31 32 var abcd = mergeRec(array);33 console.log(abcd);