排序算法---归并排序

#include<stdio.h>
void Merge_Sort(int *arr, int *temparr,int start,int mid,int end)
{
    int left_start = start ;
    int left_end   = mid ;

    int right_start = mid+1 ;
    int right_end   = end ;

    int index = start ;

    while(left_start<=left_end&&right_start<=right_end)
    {
        if(arr[left_start]>arr[right_start])
            temparr[index++] = arr[right_start++] ;
        else
            temparr[index++] = arr[left_start++] ;
    }

    while(left_start<=left_end)
        temparr[index++] = arr[left_start++] ;

    while(right_start<=right_end)
        temparr[index++] = arr[right_start++] ;

    for(index = start ;index<=end ;++index)
        arr[index] = temparr[index] ;
}
void Sort_Message(int *arr, int *temparr,int start,int end)
{
    if(start<end)
    {
        int mid = (start+end)/2 ;
        Sort_Message(arr,temparr,start,mid) ;
        Sort_Message(arr,temparr,mid+1,end) ;
        Merge_Sort(arr,temparr,start,mid,end) ;
    }
}

int main(void)
{
    int a[] = {9,2,5,3,7,4,8,0} ;
    int n = sizeof(a)/sizeof(a[0]) ;
    int i, temp[8] ;

    printf("原序列为:") ;
    for(i=0;i<n;++i)
        printf("%d ",a[i]) ;
    printf("\n") ;

    Sort_Message(a,temp,0,n-1) ;

    printf("\n排后序列:") ;
    for(i=0;i<n;++i)
        printf("%d ",a[i]) ;
    printf("\n") ;
    return 0 ;
}