[Java] Stack, reverseString

Stack

• 스택으로 reverseString 구현

package adt;
// Stack 클래스
public class Stack {
	private char [] myStack; 
	private int maxSize; 
	private int top = -1; 
	
	Stack(int s) {
		this.maxSize = s;
		myStack = new char [maxSize]; 
	}
	
	public void push(char i) {
		top++;
		myStack[top] = i;
	}
	
	public char pop() {
		int old_top = top; 
		top--; 
		return myStack[old_top];
	}
	
	public boolean isEmpty() {
		if(top == -1) {
			return true; 
		} 
		return false; 
	}
	
	public boolean isFull() {
		if(top == maxSize) {
			return true;
		} 
		return false;
	}
	
	public int getTop() {
		return top;
	}
}

// 메서드를 통한 출력
package adt;

public class App {

	public static void main(String[] args) {
		System.out.println(reverseStr("hello"));
	}
	
	public static String reverseStr(String str) {
		int len = str.length(); 
		Stack stack = new Stack(len); 
		for(int i = 0 ; i < len ; i++) {
			char ch = str.charAt(i);
			stack.push(ch);
		}
		String result = "";
		while(!stack.isEmpty()) {
			result += stack.pop(); 
		}
		return result; 
	}
}