[HackerLank] Simple Text Editor - 문제풀이

Description

주어진 스펙을 가지는 간단한 텍스트 에디터를 구현하는 문제입니다.

Solution 1. Stack

public static void main(String[] args) {

    TextEditor editor = new TextEditor("");
    Scanner in = new Scanner(System.in);
    while(in.hasNext()){
        int cm = in.nextInt();
        switch (cm){
            case 1 : editor.append(in.next()); break;
            case 2 : editor.delete(in.nextInt()); break;
            case 3 : editor.print(in.nextInt()); break;
            case 4 : editor.undo(); break;
            default: break;
        }
    }
}
public static class TextEditor<Integer> {

    private Stack<String> stack = new Stack();

    public TextEditor(String text) {
        stack.push(text);
    }

    public void append(String s){
        stack.push(stack.peek() + s);
    }
    public void delete(int n){
        String s = stack.peek();
        if(s.length() < n){
            stack.push("");
        }else{
            stack.push(s.substring(0,s.length()-n));
        }
    }
    public void print(int i){
        System.out.println(stack.peek().charAt(i-1));
    }
    public void undo(){
        if(!stack.isEmpty()){
            stack.pop();
        }
    }
}

스택을 이용하여 이전 기록들을 관리하며 값을 변경해 나갑니다.

Reference

Simple Text Editor | HackerRank