문제풀이 import java.io.*; import java.util.HashMap; import java.util.HashSet; import java.util.Map; import java.util.Set; import java.util.regex.Matcher; import java.util.regex.Pattern; interface Main{ static void main(String[]a) throws IOException { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out)); ..