[DataStructures] 스택(Stack) - 간단자바예제(Simple in java)

스택(Stack) - 간단자바예제(Simple in java)

1. 스택(Stack)

- Push : 탑에 객체가 쌓인다(add)

- Pop : 탑에 객체가 없어진다(remove)

- Peek : 탑의 값을 가져온다

2. 구현

1) 변수 초기화

private int stackSize; private int top; private int[] stackArray; public SimpleImplementation(int size){ this.stackSize = size; this.top = -1; this.stackArray= new int[stackSize]; }

2) push() and isStackFull()

public void push(int element) throws Exception{ if(this.isStackFull()){ throw new Exception("Stack is full"); } System.out.println("pushing:"+element); this.stackArray[++top] = element; } public boolean isStackFull(){ if(top == stackSize - 1){ return true; }else{ return false; } }  

3). pop() and isStackEmpty()

public int pop() throws Exception{ if(this.isStackEmpty()){ throw new Exception("Stack is empty"); } int element = stackArray[top--]; System.out.println("poping:"+element); return element; } public boolean isStackEmpty(){ if(top == -1){ return true; }else{ return false; } }  

4) peek()

public int peek(){ System.out.println("peek:"+stackArray[top]); return stackArray[top]; }  

5) main()

public static void main(String[]args){ SimpleImplementation stack = new SimpleImplementation(3); try{ stack.push(1); stack.push(2); stack.push(3); stack.pop(); stack.push(4); stack.peek(); stack.pop(); stack.pop(); stack.pop(); stack.pop(); }catch(Exception e){ System.out.println(e.getMessage()); } }