This is a version I made:#include <stdio.h>#include <stdbool.h>#define MAX_STACK_SIZE 255typedef struct{    int array[MAX_STACK_SIZE];    unsigned int count;    unsigned int max;} Stack;void initialize(Stack*);void push(Stack*, int value);int* pop(Stack*);bool isEmpty(Stack*);bool isFull(Stack*);int main(){    Stack s1;    initialize(&s1);    for(int i = 0; i < 7; i++)    {        push(&s1, i);    }    pop(&s1);    push(&s1, 88);    push(&s1, 6);    int *top;    while((top = pop(&s1)) != NULL)    {        printf(Popping %d from the top of the stack.\n, *top);    }    return 0;}void initialize(Stack *p){    p->count = 0;    p->max = MAX_STACK_SIZE;}void push(Stack *p, int value){    if(!isFull(p))    {        p->array[p->count] = value;        p->count++;    }}int* pop(Stack *p){    if (!isEmpty(p))    {        p->count--;        return p->array + p->count;    }    return NULL;}bool isEmpty(Stack *p){    return p->count == 0;}bool isFull(Stack *p){    return p->count == p->max;}This is a version of how it was done from the source I'm learning from:#include <stdio.h>#define MAX_STACK_SIZE 255#define true 1#define false 0#define bool unsigned short intstruct stack{    int *topOfStack;    int *pointer;    int count;    int max;    int theStack[MAX_STACK_SIZE];};void initStack(struct stack *stackStruct){    stackStruct->topOfStack = stackStruct->theStack;    stackStruct->pointer = stackStruct->theStack;    stackStruct->max = MAX_STACK_SIZE;    stackStruct->count = 0;}bool pushStack(struct stack *stackStruct, int inputValue){    if(stackStruct->count < stackStruct->max)    {        *stackStruct->pointer = inputValue;        stackStruct->count++;        stackStruct->pointer++;        return true;    }    else        return false;}int* popStack(struct stack *stackStruct){    if(stackStruct->count > 0)    {        stackStruct->pointer--;        stackStruct->count--;        return stackStruct->pointer;    }    return NULL;}I think there's not so much of a difference between theb, but I just wanted to be sure.  In their version, they've used 2 additional pointers in their Stack struct and I removed them because I thought it was not necessary because we could use the array address + count to get the pointer address in their example.  I think they used it for convenience reasons.  More differences are that I included <stdbool.h> instead of using macros (not really important).On top of that, I've implemented isEmpty() and isFull() methods just for convenience, but don't take it into account when comparing the two implementations since I'm sure they could do the same.  I just chose to show the 2 main functions that could be used on a stack.Other than that, since it's an array-based implementation of a stack, I think it was possible to not include the max field in the struct since we define in a macro the stack maximum size, but I added it as well to my implementation for the heck of it.Is there any differences between our implementations? Since I chose to do my own implementation I just want to make sure I that I did implemented it correctly and efficiently.
Which is a better implementation of a stack data structure (based on an array)?
c;stack;comparative review