1880 : 암호풀기(Message Decoding)

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.StringTokenizer;
 
public class Main {
 
    public static void main(String[] args) throws IOException {
        // TODO Auto-generated method stub
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        //StringTokenizer st = new StringTokenizer(in.readLine());
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
         
        String bokho, amho;
         
        bokho = in.readLine();
        amho = in.readLine();
     
        int i;
         
        for (i = 0; i < amho.length(); i++) {
            if (Character.isAlphabetic(amho.charAt(i))) {
                if (Character.isUpperCase(amho.charAt(i))) {
                    bw.write(Character.toUpperCase(bokho.charAt(amho.charAt(i)-'A')));
                    bw.flush();
                }
                else {
                    bw.write(bokho.charAt(amho.charAt(i) - 'a'));
                    bw.flush();
                }
            }
            else {
                bw.write(amho.charAt(i));
                bw.flush();
            }
        }
    }
 
}

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