[Algorithm] 특정 문자 뒤집기

알파벳만 뒤집힌 문자열 출력하기

---

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String str = sc.next();
        String answer;
            char[] s = str.toCharArray();
            int lt = 0, rt = str.length() - 1;
            while (lt < rt) {
                if (!Character.isAlphabetic(s[lt])) lt++;
                else if (!Character.isAlphabetic(s[rt])) rt--;
                else {
                    char tmp = s[lt];
                    s[lt] = s[rt];
                    s[rt] = tmp;
                    lt++;
                    rt--;
                }
            }
            answer = String.valueOf(s);
            System.out.println(answer);
    }
}

---

import java.util.Scanner;

public class Main {
    public String solution(String str) {
        String answer;
        char[] s = str.toCharArray();
        int lt = 0, rt = str.length() - 1;
        while (lt < rt) {
            if (!Character.isAlphabetic(s[lt])) lt++;
            else if (!Character.isAlphabetic(s[rt])) rt--;
            else {
                char tmp = s[lt];
                s[lt] = s[rt];
                s[rt] = tmp;
                lt++;
                rt--;
            }
        }
        answer = String.valueOf(s);
        return answer;
    }

    public static void main(String[] args) {
        Main T = new Main();
        Scanner sc = new Scanner(System.in);
        String str = sc.next();
        System.out.println(T.solution(str));
    }
}

---

Kotlin으로 문제풀이

import java.util.*

fun main() = with(Scanner(System.`in`.bufferedReader())) {
    var str = next()
    println(word(str))

}
fun word(str: String): String {

    var answer = " "
    var s = str.toCharArray()
    var lt = 0
    var rt = str.length - 1

    while (lt < rt) {
        if(!s[lt].isLetter()) lt++
        else if (!s[rt].isLetter()) rt--
        else {
            var tmp = s[lt]
            s[lt] = s[rt]
            s[rt] = tmp
            lt++
            rt--
        }
    }
    answer = s.concatToString()
    return answer
}

isLetter - 문자가 true이면 문자를 반환 합니다.

concatToString - CharArray의 문자를 문자열로 연결합니다.