백준 - 전구와 스위치(2138번) - Java

1. 문제

https://www.acmicpc.net/problem/2138

2. 풀이

밑에 풀이를 참고하여 작성하였다.
https://astrid-dm.tistory.com/429

2-1.

< char Array를 String으로 바꾸기 >

char tmpChar[] = {'1', '0'};
String S = new String(tmpChar);

< String을 char Array로 바꾸기 >

String S = "abc";
char tmpChar[] = S.toCharArray();

3. 코드

import java.util.*;
import java.io.*;

public class Main {
    
    static int N;
    static int answer;
    static String befS;
    static String afS;

	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		
		N = Integer.parseInt(br.readLine());
		answer = Integer.MAX_VALUE;
        
		befS = br.readLine();
		afS = br.readLine();
		
		solve(0);
        solve(1);
        
        if(answer == Integer.MAX_VALUE) {
            System.out.println(-1);
        } else {
            System.out.println(answer);
        }
	}
    
    public static void solve(int lightOn) {
        char befArr[] = befS.toCharArray();
		int count = 0;
        
        if(lightOn == 0) {
            befArr[0] = (befArr[0] == '0') ? '1' : '0';
            befArr[1] = (befArr[1] == '0') ? '1' : '0';
            count++;
        }
        
        for(int i = 1; i < N; i++) {
            if(befArr[i - 1] != afS.charAt(i - 1)) {
                befArr[i-1] = (befArr[i-1] == '0') ? '1' : '0';
                befArr[i] = (befArr[i] == '0') ? '1' : '0';
                if(i < N - 1) {
                    befArr[i+1] = (befArr[i+1] == '0') ? '1' : '0';
                }
                
                count++;
            }
        }
        if(afS.equals(new String(befArr))) {
            answer = Math.min(answer, count);
        }
    }

}