1-7 회문 문자열

package 섹션1_String;

import java.io.*;

public class 회문문자열 {
    public static void main(String[] args) throws IOException {

        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));

        String answer = "YES";
        String str = br.readLine().toUpperCase();
        int len= str.length();

        for(int i=0;i<len/2;i++){
            if(str.charAt(i)!= str.charAt(len-i-1)){
                answer = "NO";
                break;
            }
        }

        bw.write(answer);
        bw.flush();
        br.close();
        bw.close();
    }
}

 

 

 

✅ equlasIgnoreCase : 대소문자 구분없이 문자열이 동일한지 비교

package 섹션1_String;

import java.io.*;

public class 회문문자열 {
    public static void main(String[] args) throws IOException {

        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));

        String answer = "NO";

        String str= br.readLine();
        String reverse=new StringBuilder(str).reverse().toString();

        if(str.equalsIgnoreCase(reverse)){
            answer = "YES";
        }

        bw.write(answer);
        bw.flush();
        br.close();
        bw.close();
    }
}

 

 

" 문자열 문제는 StringBuilder의 내장함수를 적극 이용!"