Java - 백준 코딩테스트 2675번 [문자열 - 문자열 반복]

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 RepeatString {
 
    public static void main(String[] args) throws IOException {
        // 20210625 - 2675번
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        
        int num = Integer.parseInt(br.readLine());
        
        StringTokenizer st;
        for (int i = 0; i < num; i++) {
            st = new StringTokenizer(br.readLine(), " ");
            
            int repeat = Integer.parseInt(st.nextToken());
            String str = st.nextToken();
            
            for (int j = 0; j < str.length(); j++) {
                for (int k = 0; k < repeat; k++) {
                    bw.write(str.charAt(j));
                }
            }
            bw.newLine();
        }
        
        bw.flush();
        bw.close();
        br.close();
    }
}