Step-by-step write algorithm (the linear stack)

Text: Step-by-step write algorithm (linear stack)

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We talked about the queue ahead, and today we go on to another data structure: the stack. The stack is almost the lifeblood of programming, there is no function call without a stack, and of course there is no software design. So what are the special properties of the stack? In fact, the properties of the stack are mainly shown in the following two aspects:

(1) Stack data is first in and out

(2) The length of the stack depends on the height of the stack top

So what should be the design of a stack as a continuous memory type? You can try it yourself first:

(1) Design stack node

typedef struct _stack_node{    int* pdata;int length;int top;} Stack_node;

(2) Creating a stack

stack_node* alloca_stack (int number) {    stack_node* pstacknode = NULL;    if (0 = = number)    return NULL;    Pstacknode = (stack_node*) malloc (sizeof (Stack_node));    ASSERT (NULL! = Pstacknode);    memset (pstacknode, 0, sizeof (stack_node));    Pstacknode->pdata = (int*) malloc (sizeof (int) * number);    if (NULL = = pstacknode->pdata) {free    (pstacknode);        return NULL;    }    memset (pstacknode->pdata, 0, sizeof (int) * number);    pstacknode-> length = number;    pstacknode-> top= 0;    return pstacknode;}

(3) releasing the stack

STATUS free_stack (const stack_node* pstacknode) {    if (NULL = = Pstacknode)        return FALSE;    ASSERT (NULL! = pstacknode->pdata);    Free (pstacknode->pdata);    Free ((void*) pstacknode);    return TRUE;}

(4) Stack Press-in data

STATUS Stack_push (stack_node* pstacknode, int value) {    if (NULL = = Pstacknode)        return FALSE;    if (pstacknode->length = = pstacknode->top)        return FALSE;    Pstacknode->pdata[pstacknode->top + +] = value;    return TRUE;}

(5) Stack popup data

STATUS Stack_pop (stack_node* pstacknode, int* value) {    if (NULL = = Pstacknode | | NULL = = value)        return FALSE;    if (0 = = pstacknode->top)        return FALSE;    *value = pstacknode->pdata[--pstacknode->top];    return TRUE;}

(6) Count how much data is contained in the current stack

int Count_stack_number (const stack_node* pstacknode) {    return pstacknode->top;}

Recommendation: The stack is the basis of function calls, is the basis of recursive calls, is a source of many problems, it is recommended that friends usually have time to practice a good.

"Preview: The following blog introduces the contents of the linked list"

Step-by-step write algorithm (the linear stack)