通用栈实现

C++通用栈实现

#include
#include
#include
#include

// 栈中一个一个的元素 
typedef struct Node
{
	void *pdata;
	// 指向上一个结点的指针  previous next  -> pnext 
	struct Node *pnext;
}Node,*PNode;


// 栈 
typedef struct CStack
{
	// 栈中元素个数 
	int count;
	// 栈中元素大小 
	int data_size;
	// 栈顶元素 
	Node *phead;
}CStack,*PCStack;

// 判断当前栈是否为null 
bool IsEmpty(PCStack ps)
{
    return ps->phead == NULL;
}

// 将栈全部free掉 
void Destroy(PCStack ps)
{
	Node *p;
	while(ps->phead != NULL)
	{
	p = ps->phead;
	ps->phead = p->pnext;
	free(p->pdata);
	free(p);
	}
	ps->count = 0;
}


void InitStack(PCStack ps,int data_size)
{
	// assert判断条件是否返回正确，如果返回错误则报错 
	assert(ps != NULL);
	if(ps==NULL && data_size<0)
	{
		return ;
	}
	ps->count = 0;
	ps->data_size = data_size;
	ps->phead = NULL;
}

// 新建一个结点 
static Node* BuyNode(PCStack ps,void *pdata)
{
	Node *p = (Node*)malloc(sizeof(Node));
	p->pdata =(char *) malloc(ps->data_size);
	assert(p!=NULL && p->pdata!=NULL);
	char *pd = (char *)pdata;
	memcpy(p->pdata,pd,ps->data_size); 
	return p;
}

// 入栈 
bool Push(PCStack ps,void *pdata)
{
	Node *p = BuyNode(ps,pdata);
	
	p->pnext = ps->phead;
	ps->phead = p;
	ps->count++;
	
	return true;
}

//获取栈顶值，但不删除
bool GetTop(PCStack ps,void *rtval)
{
	if(IsEmpty(ps))
	{
	return false;
	}
	char *rt = (char *)rtval;
	char *tmp = (char*)ps->phead->pdata;
	memcpy(rt,tmp,ps->data_size);
	return true;
}


//获取栈顶值，并且删除
bool Pop(PCStack ps,void *rtval)
{
	if(IsEmpty(ps))
	{
		return false;
	}
	Node *p = ps->phead;
	char *rt = (char *)rtval;
	char *tmp = (char*)p->pdata;
	memcpy(rt,tmp,ps->data_size);
	ps->phead = p->pnext;
	free(p->pdata);
	free(p);
	ps->count--;
	return true;
}


int main()
{
	// 创建一个新的栈 
	CStack ss; 
	// 初始化栈  且栈的元素大小为 char*  
	InitStack(&ss,sizeof(char*));
	char *p[8] = {"123","1234","12345","abc","abcd","xyz","123abcd","123abcdxyz"};
	int i;
	// 用户接受从栈顶取出的元素 
	char* ptmp;
	for(i=0 ; i<8 ; i++)
	{
		// 总共定义了8个元素，8个元素依次入栈 
		Push(&ss,(void*)&p[i]);
	}
		
	while(!IsEmpty(&ss))
	{
		GetTop(&ss,(void*)&ptmp);
		printf("%s\n",ptmp);
		Pop(&ss,(void*)&ptmp);
	}
	Destroy(&ss); 
	
	return 0;
}


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143