[Data Structure] 스택(stack)

스택(stack)

• 데이터를 쌓아놓은 더미.
• A collection of elements that are inserted and removed according to the last-in first-out(LIFO) principle.
• 마지막으로 들어온 요소가 가장 먼저 제거됩니다.
• Input과 Output은 stack의 가장 맨 위에서만 이루어집니다.

https://ko.wikipedia.org/wiki/스택

 

• 용어(Terminology):
  • Top: The top of stack (default = -1)
  • Push: Insert an item on the top.
  • Pop: Remove the item on the top.
• 작동(Operation):
  • InitStack: Make stack empty.
  • IsFull: Check whether stack is full.
  • IsEmpty: Check whether stack is empty.
  • Peek: Read the item at the top.
  • Push: Insert an item at the top.
  • Pop: Remove the item at the top.

#define MAT_STACK 100

typedef enum {false, true} bool;
typedef int Data;

typedef struct{
	Data item[MAX_STACK];
    int top;
}Stack;

void InitStack(Stack *pstack);
bool IsFull(Stack *pstack);
bool IsEmpty(Stack *pstack);
Data Peek(Stack *pstack);
void Push(Stack *pstack, Data item);
void Pop(Stack *pstack);

void InitStack(Stack *pstack){
	pstack->top = -1;
}

bool IsFull(Stack *pstack){
	return pstack->top == MAX_STACK - 1;
}

bool IsEmpty(Stack *pstack){
	return pstack->top == -1;
}

Data Peek(Stack *pstack){
	if(IsEmpty(pstack))
    	exit(1);
    return pstack->items[pstack->top];
}

void Push(Stack *pstack, Data item){
	if(IsFull(pstack))
    	exit(1);
    pstack->items[++(pstack->top)] = item;
}

void Pop(Stack *pstack){
	if(IsEmpty(pstack))
    	exit(1)
    --(pstack->top);
}