add by jinshaohui for skip list by c

c-cpp/17_skiplist/skiplist_c/skiplist.c

@@ -0,0 +1,345 @@
+/*************************************************************************
+ > File Name: skiplist.c
+ > Author:  jinshaohui
+ > Mail:    [email protected]
+ > Time:    18-10-31
+ > Desc:    
+ ************************************************************************/
+#include<stdio.h>
+#include<stdlib.h>
+#include<string.h>
+#include<assert.h>
+#include"./skiplist.h"
+
+
+/*创建node节点*/
+node* skip_list_create_node(int level,int key,int value)
+{
+	node * tmp = NULL;
+
+	tmp =(node *)malloc(sizeof(node) + level*sizeof(node *));
+	assert(tmp != NULL);
+
+	memset(tmp,0,sizeof(node) + level*sizeof(node*));
+	tmp->key = key;
+	tmp->value = value;
+	tmp->max_level = level;
+
+    return tmp;
+}
+
+/*创建跳表的表头，max_level层数*/
+skiplist * skip_list_create(int max_level)
+{
+	int i = 0;
+	skiplist * list = NULL;
+
+	list = (skiplist *)malloc (sizeof(skiplist));
+	assert(list != NULL);
+
+	list->level = 1;
+	list->count = 0;
+
+	list->head = skip_list_create_node(max_level,0,0);
+	if(list->head == NULL)
+	{
+
+		free(list);
+		return NULL;
+	}
+
+	return list;
+}
+
+/*skiplist 销毁*/
+void skip_list_destory(skiplist * list)
+{
+	int i = 0;
+	node * tmp = NULL;
+
+	if((list == NULL) || (list->head == NULL))
+	{
+		return;
+	}
+	while(list->head->next[0] != NULL)
+	{
+        tmp = list->head->next[0];
+        list->head->next[0] = tmp->next[0];
+		free(tmp);
+	}
+
+	free(list);
+	return;
+}
+
+/*插入元素获得层数，是随机产生的*/
+int skip_list_level(skiplist * list)
+{
+	int i = 0;
+	int level = 1;
+	for (i = 1; i < list->head->max_level; i++)
+	{
+		if ((rand()%2) == 1)
+		{
+			level++;
+		}
+	}
+
+	return level;
+}
+int skip_list_insert(skiplist *list,int key,int value)
+{
+	int i = 0;
+	int level = 0;
+	node **update = NULL;/*用来更新每层的指针*/
+	node *tmp = NULL;
+	node *prev = NULL;
+
+	if (list == NULL)
+	{
+		return 1;
+	}
+
+    /*申请update空间用于保存每层的指针*/
+	update = (node **)malloc(sizeof(node *)*list->head->max_level);
+	if (update == NULL)
+	{
+		return 2;
+	}
+
+    /*逐层查询节点的*/
+	prev = list->head;
+	for (i = (list->level -1); i >= 0; i--)
+	{
+	    /*初始化每level层的头指针*/
+		while(((tmp = prev->next[i]) != NULL) && (tmp->key < key))
+		{
+			prev  = tmp;
+		}
+		update[i] = prev;
+	}
+
+	/*当前key已经存在，返回错误*/
+	if ((tmp!= NULL) && (tmp->key == key))
+	{
+		return 3;
+	}
+	/*获取插入元素的随机层数，并更新跳表的最大层数*/
+	level = skip_list_level(list);
+	/*创建当前数据节点*/
+	tmp = skip_list_create_node(level,key,value);
+	if (tmp == NULL)
+	{
+		return 4;
+	}
+
+	/*更新最大层数*/
+	if (level > list->level)
+	{
+		for (i = list->level;i < level; i ++)
+		{
+			update[i] = list->head;
+		}
+		list->level = level;
+	}
+
+	/*逐层更新节点的指针*/
+	for(i = 0; i < level; i++)
+	{
+        tmp->next[i] = update[i]->next[i];
+		update[i]->next[i] = tmp; 
+	}
+
+    list->count++;
+	return 0;
+}
+
+int skip_list_delete(skiplist * list, int key ,int *value)
+{
+	int i = 0;
+	node **update = NULL;/*用来更新每层的指针*/
+	node *tmp = NULL;
+	node *prev = NULL;
+
+	if ((list == NULL) && (value == NULL)&& (list->count == 0))
+	{
+		return 1;
+	}
+    /*申请update空间用于保存每层的指针*/
+	update = (node **)malloc(sizeof(node *)*list->level);
+	if (update == NULL)
+	{
+		return 2;
+	}
+    /*逐层查询节点的*/
+	prev = list->head;
+	for (i = (list->level -1); i >= 0; i--)
+	{
+	    /*初始化每level层的头指针*/
+		while(((tmp = prev->next[i]) != NULL) && (tmp->key < key))
+		{
+			prev = tmp;
+		}
+		update[i] = prev;
+	}
+
+	if ((tmp != NULL)
+		&& (tmp->key == key))
+	{
+		*value = tmp->value;
+	    /*逐层删除*/
+		for(i = 0; i < list->level; i++)
+		{
+			if(update[i]->next[i] == tmp)
+			{
+			     update[i]->next[i] = tmp->next[i];       
+			}	
+		}
+
+		free(tmp);
+		tmp = NULL;
+
+		/*更新level的层数*/
+		for (i = list->level - 1; i >= 0; i++)
+		{
+			if (list->head->next[i] == NULL )
+			{
+				list->level--;
+			}
+			else
+			{
+				break;
+			}
+		}
+
+		list->count--;
+
+	}
+	else
+	{
+		return 3;/*未找到节点*/
+	}
+
+    return 0 ;
+}
+
+/*查询当前key是否在跳表中，如果存在返回查询的value数值，不存在返回-1*/
+int skip_list_search(skiplist *list,int key,int *value)
+{
+	int i = 0;
+    node *prev = NULL;
+	node *tmp = NULL;
+
+	if((list == NULL) || (list->count == 0) || (value == NULL))
+	{
+		return 1;
+	}
+    prev = list->head;
+	for(i = list->level - 1; i >= 0; i--)
+	{
+		while(((tmp = prev->next[i]) != NULL) && (tmp->key <= key))
+		{
+			if (tmp->key == key)
+			{
+		        *value = tmp->value;
+		        return 0;
+			}
+			prev = tmp;
+		}
+	}
+
+    return -1;
+}
+
+void skip_list_dump(skiplist *list)
+{
+	int i = 0;
+    node *ptmp = NULL;
+    printf("\r\n----------------------------------------------");
+	printf("\r\n skip list level[%d],count[%d]",list->level,list->count);
+	for(i = list->level - 1; i >= 0; i --)
+	{
+		ptmp = list->head->next[i];
+		printf("\r\n level[%d]:",i);
+		while(ptmp != NULL)
+		{
+			printf("%d-%d ",ptmp->key,ptmp->value);
+			ptmp = ptmp->next[i];
+		}
+	}
+    printf("\r\n----------------------------------------------");
+	return;
+}
+
+int main()
+{
+	int res = 0;
+	int key = 0;
+	int value = 0;
+    skiplist *list = NULL;
+
+
+	list = skip_list_create(5);
+	assert(list != NULL);
+
+	while(1)
+	{
+		printf("\r\n 请输入key 和 value，当key = 1000时，退出输入：");
+		scanf("%d%d",&key,&value);
+		if (key == 1000)
+		{
+			break;
+		}
+		res = skip_list_insert(list,key,value);
+		if (res != 0)
+		{
+			printf("\r\n skip list insert %d,failed,res=%d.",key,res);
+		}
+	}
+	skip_list_dump(list);
+
+	while(1)
+	{
+		printf("\r\n 通过key 查询value的数值，当key = 1000时，退出查询");
+		scanf("%d",&key);
+		if(key == 1000)
+		{
+			break;
+		}
+		res = skip_list_search(list,key,&value);
+		if (res != 0)
+		{
+			printf("\r\n skip list search %d,failed,res=%d.",key,res);
+		}
+		else
+		{
+			printf("\r\n skip list search %d,sucessful,value=%d.",key,value);
+
+		}
+	}
+	skip_list_dump(list);
+	while(1)
+	{
+		printf("\r\n 通过key 删除节点，当key = 1000时，退出删除");
+		scanf("%d",&key);
+		if(key == 1000)
+		{
+			break;
+		}
+		res = skip_list_delete(list,key,&value);
+		if (res != 0)
+		{
+			printf("\r\n skip list search %d,failed,res=%d.",key,res);
+		}
+		else
+		{
+			printf("\r\n skip list search %d,sucessful,value=%d.",key,value);
+
+		}
+	}
+
+	skip_list_dump(list);
+	skip_list_destory(list);
+
+	return 0;
+}

c-cpp/17_skiplist/skiplist_c/skiplist.h

@@ -0,0 +1,33 @@
+/*************************************************************************
+ > File Name: skiplist.h
+ > Author:  jinshaohui
+ > Mail:    [email protected]
+ > Time:    18-10-31
+ > Desc:    
+ ************************************************************************/
+#ifndef __SKIP_LIST_H__
+#define __SKIP_LIST_H__
+
+
+typedef struct _node
+{
+	int key;    /*key是唯一的*/
+	int value;  /*存储的内容*/
+	int max_level; /*当前节点最大层数*/
+	struct _node *next[0];/*level层链表结构*/
+}node;
+
+typedef struct _skiplist
+{
+	int level;
+	int count;
+	node *head;
+}skiplist;
+
+/*根据当前结构体元素的地址，获取到结构体首地址*/
+#define offsetof(TYPE,MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+#define container(ptr,type,member) ({\
+  const typeof( ((type *)0)->member) *__mptr = (ptr);\
+  (type *) ( (char *)__mptr - offsetof(type,member));})
+
+#endif