RollCal.java

/**
 * @Author Mehdi Maick
 * Created on 17/09/2016.
 */

import java.util.*;
import java.io.*;

public class RollCal {
    static class Name implements Comparable<Name> {
        String firstName, lastName;

        public Name(String firstName, String lastName) {
            this.firstName = firstName;
            this.lastName = lastName;
        }

        @Override
        public int compareTo(Name o) {
            if (o.lastName.equals(lastName)) {
                return firstName.compareTo(o.firstName);
            }
            return lastName.compareTo(o.lastName);
        }
    }

    public static void solve(FastReader fs, PrintWriter pw) {
        String[] data;
        String line;

        ArrayList<Name> list = new ArrayList<>();
        Map<String, Integer> map = new HashMap<>();

        while ((line = fs.nextLine()) != null) {
            data = line.split(" ");
            list.add(new Name(data[0], data[1]));
            if (map.get(data[0]) == null) {
                map.put(data[0], 1);
            } else {
                int i = map.get(data[0]);
                map.put(data[0], i + 1);
            }
        }

        list.sort(null);

        for (Name n : list) {
            if (map.get(n.firstName) == 1) {

                pw.println(n.firstName);

            } else {

                pw.println(n.firstName + " " + n.lastName);

            }
        }

    }

    public static void main(String[] args) throws Exception {
        FastReader fs = new FastReader(System.in);
        PrintWriter pw = new PrintWriter(new OutputStreamWriter(System.out));

        solve(fs, pw);

        fs.close();
        pw.close();
    }

    static class FastReader {

        BufferedReader reader;
        StringTokenizer st;

        FastReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream));
            st = null;
        }

        String next() {
            while (st == null || !st.hasMoreTokens()) {
                try {
                    String line = reader.readLine();
                    if (line == null) {
                        return null;
                    }
                    st = new StringTokenizer(line);
                } catch (Exception e) {
                    throw new RuntimeException();
                }
            }
            return st.nextToken();
        }

        String nextLine() {
            String s = null;
            try {
                s = reader.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return s;
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }

        char nextChar() {
            return next().charAt(0);
        }

        int[] nextIntArray(int n) {
            int[] arr = new int[n];
            int i = 0;
            while (i < n) {
                arr[i++] = nextInt();
            }
            return arr;
        }

        long[] nextLongArray(int n) {
            long[] arr = new long[n];
            int i = 0;
            while (i < n) {
                arr[i++] = nextLong();
            }
            return arr;
        }

        int[] nextIntArrayOneBased(int n) {
            int[] arr = new int[n + 1];
            int i = 1;
            while (i <= n) {
                arr[i++] = nextInt();
            }
            return arr;
        }

        long[] nextLongArrayOneBased(int n) {
            long[] arr = new long[n + 1];
            int i = 1;
            while (i <= n) {
                arr[i++] = nextLong();
            }
            return arr;
        }

        void close() {
            try {
                reader.close();
            } catch (IOException e) {
                System.err.println("There's been an error trying closing the reader ");
                e.printStackTrace();
            }
        }
    }


}