문제

풀이
public class Main {
public static void main(String[] args) throws Exception {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
int n = Integer.parseInt(br.readLine());
String[] str;
for (int i = 0; i < n; i++) {
str = br.readLine().split(" ");
for (int j = 0; j < str[1].length(); j++) {
for (int k = 0; k < Integer.parseInt(str[0]); k++) {
bw.write(str[1].charAt(j)+"");
}
}
bw.write("\n");
}
bw.flush();
bw.close();
br.close();
}
}