2. 스택

#pragma once
#ifndef ARRAYSTACK_H
#define ARRAYSTACK_H

#include <stdio.h>
#include <stdlib.h>

typedef int ElementType;

typedef struct tagNode {
	ElementType Data;
} Node;

typedef struct tagArrayStack {
	int Capacity;
	int Top;
	Node* Nodes;
}ArrayStack;

void AS_CreateStack(ArrayStack** Stack, int Capacity);
void AS_DestroyStack(ArrayStack* Stack);
void AS_Push(ArrayStack* Stack, ElementType Data);
ElementType AS_Pop(ArrayStack* Stack);
ElementType AS_Top(ArrayStack* Stack);
int As_GetSize(ArrayStack* Stack);
int AS_IsEmpty(ArrayStack* Stack);

#endif

#include "ArrayStack.h"

void AS_CreateStack(ArrayStack** Stack, int Capacity) {
	/* 스택을 자유 저장소에 생성 */
	(*Stack) = (ArrayStack*)malloc(sizeof(ArrayStack));
	
	/* 입력된 Capacity 만큼의 노드를 자유 저장소에 생성 */
	(*Stack)->Nodes = (Node*)malloc(sizeof(Node) * Capacity);

	/* Capacity 및 Top 초기화 */
	(*Stack)->Capacity = Capacity;
	(*Stack)->Top = 0;
}

void AS_DestroyStack(ArrayStack* Stack) {
	/* 노드를 자유 저장소에서 해제 */
	free(Stack->Nodes);

	/* 스택을 자유 저장소에서 해제 */
	free(Stack);
}

void AS_Push(ArrayStack* Stack, ElementType Data) {
	int Position = Stack->Top;

	Stack->Nodes[Position].Data = Data;
	Stack->Top++;
}

ElementType AS_Pop(ArrayStack* Stack) {
	int Position = --(Stack->Top);

	return Stack->Nodes[Position].Data;
}

ElementType AS_Top(ArrayStack* Stack) {
	int Position = Stack->Top - 1;

	return Stack->Nodes[Position].Data;
}

int AS_GetSize(ArrayStack* Stack) {
	return Stack->Top;
}

int AS_IsEmpty(ArrayStack* Stack) {
	return (Stack->Top == 0);
}

int main() {
	int i = 0;
	ArrayStack* Stack = NULL;

	AS_CreateStack(&Stack, 10);

	AS_Push(Stack, 3);
	AS_Push(Stack, 37);
	AS_Push(Stack, 11);
	AS_Push(Stack, 12);

	printf("Capacity : %d, Size : %d, Top : %d\n\n", Stack->Capacity, AS_GetSize(Stack), AS_Top(Stack));

	for (i = 0; i < 4; i++) {
		if (AS_IsEmpty(Stack))
			break;

		printf("Poped : %d, ", AS_Pop(Stack));

		if (!AS_IsEmpty(Stack))
			printf("Current Top: %d\n", AS_Top(Stack));
		else
			printf("Stack Is Empty.\n");
	}

	AS_DestroyStack(Stack);

	return 0;
}