基數排序

基於非比較的排序 通過以數據不同位分別爲基準裝桶的操作達到排序的目的 有LSD和MSD 即低位優先和高位優先兩種裝桶方法

---C語言實現

---以兩位數爲例

---LSD

#include <stdio.h>
#include <stdlib.h>
#include <windows.h>

#define STANDARDDATASEP 10

typedef struct hashnode
{
	int value;
	struct hashnode *pNext;
}HashNode;

//遍歷數組
void LoopForArr(int arr[],int length)
{
	int count;
	if(arr == NULL || length <=0)return ;
	for(count = 0;count<length;count++)
	{
		printf("%d  ",arr[count]);
	}
	printf("\n");
}

//利用哈希分桶 
void CreateHashForRadixSort(HashNode** Head,int SepDigit,int arr[],int length)
{
	int count;
	int sepdata = 1;
	HashNode *Temp = NULL;
	HashNode *Temp_in = NULL;
	while(--SepDigit)
	{
		sepdata*=STANDARDDATASEP;
	}

	//尾添加 穩定
	for(count = 0;count<length;count++)
	{
		Temp = (HashNode *)malloc(sizeof(HashNode));
		Temp->value = arr[count];
		Temp->pNext = NULL;
		if( !Head[arr[count]/sepdata%10] )
		{
			Head[arr[count]/sepdata%10] = Temp;
		}
		else
		{
			Temp_in = Head[arr[count]/sepdata%10];
			while(Temp_in->pNext)
			{
				Temp_in = Temp_in->pNext;
			}
			Temp_in->pNext = Temp;
		}
	}
}

//基數排序 LSD
void RadixSort(int arr[],int length)
{
	int count;
	int count_in;
	int min;
	int max;
	int max_digit;
	int count_hash;
	HashNode**Head = NULL;
	HashNode*Temp = NULL;
	if(arr == NULL || length <=0)return ;

	//找最大值 最小值
	min = max = arr[0];
	for(count = 1;count<length;count++)
	{
		min = arr[count]<min?arr[count]:min;
		max = arr[count]>max?arr[count]:max;
	}
	//數據分析
	max_digit = 0;
	while(max)
	{
		max_digit++;
		max/=STANDARDDATASEP;
	}

	//申請桶
	Head = (HashNode **)malloc(sizeof(HashNode* )*STANDARDDATASEP);
	memset(Head,0,sizeof(HashNode* )*STANDARDDATASEP);
	for(count = 1;count<=max_digit;count++)
	{
		//哈希分桶
		CreateHashForRadixSort(Head,count,arr,length);
		//倒回原數組
		count_in = 0;
		count_hash = 0;
		while(count_in<length)
		{
			while(!Head[count_hash])
				count_hash++;
			Temp = Head[count_hash];
			while(Temp)
			{
				arr[count_in++] = Temp->value;
				Temp = Temp->pNext;
			}
			count_hash++;
		}
		//釋放桶內空間
		--count_hash;
		while(count_hash>=0)
		{
			Temp = Head[count_hash];
			while(Temp)
			{
				Head[count_hash] = Temp;
				Temp = Temp->pNext;
				free(Head[count_hash]);
				Head[count_hash] = NULL;
			}
			count_hash--;
		}
	}
	free(Head);
	Head = NULL;
}

int main()
{
	int count = 0;
	int arr[] = {36,49,30,12,28,16,17,31,26,55,66,91};
	RadixSort(arr,sizeof(arr)/sizeof(arr[0]));
	for(;count < sizeof(arr)/sizeof(arr[0]);count++)
	{
		printf("%d ",arr[count]);
	}
	
	system("pause");     
	return 0;
}

排序