import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.HashSet; import java.util.StringTokenizer; public class Main { public static void main(String[] args) throws IOException { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); StringBuilder sb = new StringBuilder(); int n = Integer.parseInt(br.readLine()); StringToke..