Stack-Array Implementation

 

Using arrays to implement stacks avoids the use of pointers, but the defect is that the size of arrays must be determined in advance. In general, this is not a big problem. :

Array Implementation Stack:

First, define a structure. topofstack indicates the top of the stack. When topofstack is-1, it indicates the empty stack. Array array used to store stack Elements

When pushing, ++ topofstack then adds elements to the array. Direct topofstack --;

C language implementation:

#ifndef _stack_hstruct stack;typedef struct stack *Stack;typedef int ElementType;int isEmpty(Stack s);int isFull(Stack s);Stack CreateStack(int MaxElements);void Push(ElementType x,Stack s);ElementType Top(Stack s);void Pop(Stack s);ElementType TopAndPop(Stack s);#endif

#include<stdio.h>#include<stdlib.h>#include"stack_array.h"#define ElementTOS (-1)#define MinStackSize (5)struct stack{    int Capacity;    int TopOfStack;    ElementType *Array;};int isEmpty(Stack s){    return s->TopOfStack == ElementTOS;}int isFull(Stack s){    return s->TopOfStack == s->Capacity;}Stack CreateStack(int MaxElements){    Stack s;    if(MaxElements<MinStackSize)    {        printf("The stack is too small!\n");        return NULL;    }    s = (Stack)malloc(sizeof(struct stack));    if(s==NULL)    {        printf("out of space!\n");        return NULL;    }    s->Capacity = MaxElements-1;    s->TopOfStack = ElementTOS;    s->Array = (ElementType *)malloc(MaxElements*sizeof(ElementType));    return s;}void Push(ElementType x,Stack s){    if(!isFull(s))        s->Array[++s->TopOfStack] = x;    else         printf("The stack is Full!\n");}ElementType Top(Stack s){    if(!isEmpty(s))        return s->Array[s->TopOfStack];    else    {        printf("The stack is Empty!\n");        return 0;    }}void Pop(Stack s){    if(!isEmpty(s))        s->Array[s->TopOfStack--];    else         printf("The stack is Empty!\n");}ElementType TopAndPop(Stack s){    if(!isEmpty(s))        return s->Array[s->TopOfStack--];    else    {        printf("The stack is empty!\n");        return 0;    }}int main(){    Stack s;    s = CreateStack(6);    Push(1,s);    Push(2,s);    Push(3,s);    Push(4,s);    Push(5,s);    Push(6,s);    Push(7,s);        for(int i=0;i<6;i++)    {        printf("The top of stack is %d\n",Top(s));        Pop(s);    }    Pop(s);    return 0;}