版权声明：本文为博主原创文章，如有需要, 请注明转载地址：http://blog.csdn.net/tech_pro。若是侵权用于商业用途，请联系博主，否则将追究责任。 https://blog.csdn.net/TECH_PRO/article/details/78016234
1、递归归并排序
具体实现如下：
/* 递归排序 */
void Merge_sort_r( ElementType A[], int N )
{
ElementType *TmpA;
TmpA = malloc( N * sizeof( ElementType ) );
if ( TmpA != NULL )
{
MSort_r( A, TmpA, 0, N-1 );
free( TmpA );
}
else printf("Merge_sort_r malloc error!\n");
}/* 递归进行子序列的归并 */
static void MSort_r( ElementType A[], ElementType TmpA[], int L, int RightEnd )
{
int Center;
if ( L < RightEnd )
{
Center = ( L + RightEnd ) / 2;
MSort_r( A, TmpA, L, Center );
MSort_r( A, TmpA, Center+1, RightEnd );
Merge_r( A, TmpA, L, Center+1, RightEnd );
}
}/* 有序子列的归并 */
static void Merge_r( ElementType A[], ElementType TmpA[], int L, int R, int RightEnd )
{
int LeftEnd;
int Tmp;
int NumElements;
int i;
LeftEnd = R - 1; /* 左边终点位置。假设左右两列挨着*/
Tmp = L; /* 存放结果的数组的初始位置*/
NumElements = RightEnd - L + 1;
while( L <= LeftEnd && R <= RightEnd )
{
if ( A[L] <= A[R] ) TmpA[Tmp++] = A[L++];
else TmpA[Tmp++] = A[R++];
}
while( L <= LeftEnd ) /* 直接复制左边剩下的*/
TmpA[Tmp++] = A[L++];
while( R <= RightEnd ) /*直接复制右边剩下的*/
TmpA[Tmp++] = A[R++];
/* 将数据复制回原数组 */
for( i = 0; i < NumElements; i++, RightEnd -- )
A[RightEnd] = TmpA[RightEnd];
}
2、非递归归并排序
具体实现如下：/* 非递归归并排序 */
void Merge_sort( ElementType A[], int N )
{
int length = 1; /* 初始化子序列长度*/
ElementType *TmpA;
TmpA = malloc( N * sizeof( ElementType ) );
if ( TmpA != NULL )
{
while( length < N )
{
Merge_pass( A, TmpA, N, length );
length *= 2;
Merge_pass( TmpA, A, N, length );
length *= 2;
}
free( TmpA );
}
else printf("Merge_sort malloc error!\n");
}/* 对指定长度子序列进行归并, length表示有序之列的长度 */
static void Merge_pass( ElementType A[], ElementType TmpA[], int N, int length )
{
int i, j;
for ( i=0; i <= N-2*length; i+=2*length )
Merge( A, TmpA, i, i+length, i+2*length-1 );
if ( i+length < N ) /* 归并最后2个子列*/
Merge( A, TmpA, i, i+length, N-1);
else /* 最后只剩1个子列*/
for ( j = i; j < N; j++ ) TmpA[j] = A[j];
}/* 有序子列的归并 */
static void Merge( ElementType A[], ElementType TmpA[], int L, int R, int RightEnd )
{
int LeftEnd;
int Tmp;
int NumElements;
int i;
LeftEnd = R - 1; /* 左边终点位置。假设左右两列挨着*/
Tmp = L; /* 存放结果的数组的初始位置*/
NumElements = RightEnd - L + 1;
while( L <= LeftEnd && R <= RightEnd )
{
if ( A[L] <= A[R] ) TmpA[Tmp++] = A[L++];
else TmpA[Tmp++] = A[R++];
}
while( L <= LeftEnd ) /* 直接复制左边剩下的*/
TmpA[Tmp++] = A[L++];
while( R <= RightEnd ) /*直接复制右边剩下的*/
TmpA[Tmp++] = A[R++];
}
3、完整示例代码
/* 归并排序的递归和非递归实现 */
#include <stdio.h>
#include <stdlib.h>
/* 定义一些辅助数据结构或者类型 */
typedef int ElementType;
/******************************************递归排序******************************************/
/* 有序子列的归并 */
static void Merge_r( ElementType A[], ElementType TmpA[], int L, int R, int RightEnd )
{
int LeftEnd;
int Tmp;
int NumElements;
int i;
LeftEnd = R - 1; /* 左边终点位置。假设左右两列挨着*/
Tmp = L; /* 存放结果的数组的初始位置*/
NumElements = RightEnd - L + 1;
while( L <= LeftEnd && R <= RightEnd )
{
if ( A[L] <= A[R] ) TmpA[Tmp++] = A[L++];
else TmpA[Tmp++] = A[R++];
}
while( L <= LeftEnd ) /* 直接复制左边剩下的*/
TmpA[Tmp++] = A[L++];
while( R <= RightEnd ) /*直接复制右边剩下的*/
TmpA[Tmp++] = A[R++];
/* 将数据复制回原数组 */
for( i = 0; i < NumElements; i++, RightEnd -- )
A[RightEnd] = TmpA[RightEnd];
}
/* 递归进行子序列的归并 */
static void MSort_r( ElementType A[], ElementType TmpA[], int L, int RightEnd )
{
int Center;
if ( L < RightEnd )
{
Center = ( L + RightEnd ) / 2;
MSort_r( A, TmpA, L, Center );
MSort_r( A, TmpA, Center+1, RightEnd );
Merge_r( A, TmpA, L, Center+1, RightEnd );
}
}
/* 递归排序 */
void Merge_sort_r( ElementType A[], int N )
{
ElementType *TmpA;
TmpA = malloc( N * sizeof( ElementType ) );
if ( TmpA != NULL )
{
MSort_r( A, TmpA, 0, N-1 );
free( TmpA );
}
else printf("Merge_sort_r malloc error!\n");
}
/*****************************************非递归排序*****************************************/
/* 有序子列的归并 */
static void Merge( ElementType A[], ElementType TmpA[], int L, int R, int RightEnd )
{
int LeftEnd;
int Tmp;
int NumElements;
int i;
LeftEnd = R - 1; /* 左边终点位置。假设左右两列挨着*/
Tmp = L; /* 存放结果的数组的初始位置*/
NumElements = RightEnd - L + 1;
while( L <= LeftEnd && R <= RightEnd )
{
if ( A[L] <= A[R] ) TmpA[Tmp++] = A[L++];
else TmpA[Tmp++] = A[R++];
}
while( L <= LeftEnd ) /* 直接复制左边剩下的*/
TmpA[Tmp++] = A[L++];
while( R <= RightEnd ) /*直接复制右边剩下的*/
TmpA[Tmp++] = A[R++];
}
/* 对指定长度子序列进行归并, length表示有序之列的长度 */
static void Merge_pass( ElementType A[], ElementType TmpA[], int N, int length )
{
int i, j;
for ( i=0; i <= N-2*length; i+=2*length )
Merge( A, TmpA, i, i+length, i+2*length-1 );
if ( i+length < N ) /* 归并最后2个子列*/
Merge( A, TmpA, i, i+length, N-1);
else /* 最后只剩1个子列*/
for ( j = i; j < N; j++ ) TmpA[j] = A[j];
}
/* 非递归归并排序 */
void Merge_sort( ElementType A[], int N )
{
int length = 1; /* 初始化子序列长度*/
ElementType *TmpA;
TmpA = malloc( N * sizeof( ElementType ) );
if ( TmpA != NULL )
{
while( length < N )
{
Merge_pass( A, TmpA, N, length );
length *= 2;
Merge_pass( TmpA, A, N, length );
length *= 2;
}
free( TmpA );
}
else printf("Merge_sort malloc error!\n");
}
/* 程序入口 */
int main()
{
int i;
ElementType temp;
ElementType array[10];
printf("Input 10 numbers : ");
for(i = 0; i < 10; i++)
{
scanf("%d", &temp);
array[i] = temp;
}
/* 原始数据输出 */
printf("***********************************Origin************************************\n");
for(i = 0; i < 10; i++)
printf("%d ", array[i]);
printf("\n");
/* 选择排序后输出 */
printf("***********************************Merge_r*********************************\n");
Merge_sort_r(array, sizeof(array)/sizeof(array[0]));
for(i = 0; i < 10; i++)
printf("%d ", array[i]);
printf("\n");
printf("Input 10 numbers : ");
for(i = 0; i < 10; i++)
{
scanf("%d", &temp);
array[i] = temp;
}
/* 原始数据输出 */
printf("***********************************Origin************************************\n");
for(i = 0; i < 10; i++)
printf("%d ", array[i]);
printf("\n");
/* 选择排序后输出 */
printf("***********************************Merge***********************************\n");
Merge_sort(array, sizeof(array)/sizeof(array[0]));
for(i = 0; i < 10; i++)
printf("%d ", array[i]);
printf("\n");
return 0;
}