归并排序

#include<stdio.h>
#include<malloc.h>
#define MAX 255

//自顶向下分治法 归并排序
int R[MAX];

void Merge(int low,int mid,int high)
{
	int i=low,j=mid+1,p=0;
	int *R1;
	R1=(int *)malloc((high-low+1)*sizeof(int));
	if(!R1)
	{
		puts("Insufficient memory avaliable!");
		return;
	}	
	while(i<=mid&&j<=high)
	{
		R1[p++]=(R[i]<=R[j])?R[i++]:R[j++];
	}
	while(i<=mid)
	{
		R1[p++]=R[i++];
	}
	while(j<=high)
	{
		R1[p++]=R[j++];
	}
	for(p=0,i=low;i<high;p++,i++)
	{
		R[i]=R1[p];
	}
} 


void Merge_sort(int low,int high)
{
	int mid;
	if(low<high)
	{
		mid=(high+low)/2;
		Merge_sort(low,mid);
		Merge_sort(mid+1,high);
		Merge(low,mid,high);
	}
}

int main()
{
	//测试函数
	 printf("归并排序示例:
");
	 int n,i;
	 printf("Please input the number under %d
",MAX);
	 scanf("%d",&n);
	 if(n>MAX)
	 {
	 	printf("The number is not right!
");
	 	return 0;
	 }
	 printf("Please input the array one by one:
");
	 for(i=1;i<=n;i++)
	 {
	 	scanf("%d",&R[i]);
	 }
	printf("The array you input is:
");
	for(i=1;i<=n;i++)
	{
		printf("%d ",R[i]);
	}	 
	printf("The array after Heap_sort is:
");
	Merge_sort(1,n);
	for(i=1;i<=n;i++)
	{
		printf("%d ",R[i]);
	}
		 
	 return 0;
}

  

原文地址:https://www.cnblogs.com/qysqys/p/5428563.html