/**
 * Created by DELL on 2017/4/23.
 * 二路歸併
 */
public class ErLuGuiBInSort {
    public static void main(String[] args){
        int[] in = {46,12,33,72,68,19,80,33};
        int[] rein = new int[in.length]; //用於複製保留原紀錄序列,輔助空間
int left = 0; //序列in下限
int right = in.length-1; //序列in上限
MergeSort(in,rein,left,right);
        for
 
(int i=0;i<in.length;i++){
            System.out.print(in[i]+" ");
        }
    }
    public static void MergeSort(int[] in,int[] rein,int left,int right){
        int middle;
        if(left<right){
            middle = (left+right)/2;
            MergeSort(in,rein,left,middle);
            MergeSort
 
(in,rein,middle+1,right);
            Merge(in,rein,left,right,middle);
        }
    }
    public static void Merge(int[] in,int[] rein,int left,int right,int middle){
        int i,p1,p2;
        for(i=left;i<=right;i++){
           // System.out.println("luhan "+in[i]);
rein[i] = in[i];
        }
        p1 = left;
        p2 = middle+1
 
;
        i = left;
        while(p1<=middle && p2<=right){
            if(rein[p1]<=rein[p2]){
                in[i] = rein[p1];
                p1++;
            }else{

                in[i] = rein[p2];
                p2++;
            }
            i++;
        }
        while(p1<=middle){
            in[i] = rein[p1++];
            i++;
        }
        while(p2<=right){
          //  System.out.println("luhandd "+rein[p2]);
in[i] = rein[p2++];
            i++;
        }
    }
}