java合并排序

package com.alo.offer;/** * 合并排序 * @author Administrator * */public class MergeSort {public static void main(String[] args) {int []a ={564,378,954,1255,684,57,15,389,687,45,98,125,348};new MergeSort().MergeSort(a,0,a.length-1);for(int i:a) {System.out.print(i+" ");}}public void MergeSort(int []a,int low,int high) {int mid=0;while(low<high) {mid=low+(high-low)/2;MergeSort(a,low,mid);MergeSort(a,mid+1,high);Merge(a,low,mid,high);return;}}private void Merge(int[] a, int low, int mid, int high) {// TODO Auto-generated method stubint i=low,j=mid+1,k=0;int []b = new int[high-low+1];while(i<=mid&&j<=high) {if(a[i]<=a[j]) {b[k++]=a[i++];}else {b[k++]=a[j++];}}while(i<=mid) {b[k++]=a[i++];}while(j<=high) {b[k++]=a[j++];}for(int x=0,m=low;m<=high;m++) {a[m]=b[x++];}}}