First-rate specialists graduate from Berland State Institute of Peace and Friendship. You are one of the most talented students in this university. The education is not easy because you need to have fundamental knowledge in different areas, which sometimes are not related to each other. 

For example, you should know linguistics very well. You learn a structure of Reberland language as foreign language. In this language words are constructed according to the following rules. First you need to choose the "root" of the word — some string which has more than 4 letters. Then several strings with the length 2 or 3 symbols are appended to this word. The only restriction —  it is not allowed to append the same string twice in a row. All these strings are considered to be suffixes of the word (this time we use word "suffix" to describe a morpheme but not the few last characters of the string as you may used to). 

Here is one exercise that you have found in your task list. You are given the word s. Find all distinct strings with the length 2 or 3, which can be suffixes of this word according to the word constructing rules in Reberland language. 

Two strings are considered distinct if they have different length or there is a position in which corresponding characters do not match. 

Let's look at the example: the word abacabaca is given. This word can be obtained in the following ways: <image>, where the root of the word is overlined, and suffixes are marked by "corners". Thus, the set of possible suffixes for this word is {aca, ba, ca}. 

Input

The only line contains a string s (5 ≤ |s| ≤ 104) consisting of lowercase English letters.

Output

On the first line print integer k — a number of distinct possible suffixes. On the next k lines print suffixes. 

Print suffixes in lexicographical (alphabetical) order. 

Examples

Input

abacabaca


Output

3
aca
ba
ca


Input

abaca


Output

0

Note

The first test was analysed in the problem statement. 

In the second example the length of the string equals 5. The length of the root equals 5, so no string can be used as a suffix.
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.Writer;
import java.lang.reflect.Constructor;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.InputMismatchException;
import java.util.StringTokenizer;

public class CodeA {
  private static final boolean SHOULD_BUFFER_OUTPUT = false;

  static final SuperWriter sw = new SuperWriter(System.out);

  static final SuperScanner sc = new SuperScanner();

  static String s;
  static HashSet<String> values = new HashSet<String>();
  static Boolean[][] dp;

  static boolean dp(int current, int last) {
    if (current == s.length()) {
      return true;
    }
    if (dp[current][last] != null) {
      return dp[current][last];
    }
    String lastString = last == 0 ? "" : s.substring(current - last, current);
    boolean isPossible = false;
    if (current + 2 <= s.length()) {
      String possible = s.substring(current, current + 2);
      if (!possible.equals(lastString)) {
        if (dp(current + 2, 2)) {
          values.add(possible);
          isPossible = true;
        }
      }
    }
    if (current + 3 <= s.length()) {
      String possible = s.substring(current, current + 3);
      if (!possible.equals(lastString)) {
        if (dp(current + 3, 3)) {
          values.add(possible);
          isPossible = true;
        }
      }
    }
    return dp[current][last] = isPossible;
  }

  public static void main() {
    s = sc.next();
    dp = new Boolean[s.length()][4];
    for (int i = 5; i < s.length(); i++) {
      dp(i, 0);
    }
    ArrayList<String> toPrint = new ArrayList<>(values);
    Collections.sort(toPrint);
    sw.printLine(toPrint.size());
    for (String x : toPrint) {
      sw.printLine(x);
    }
  }

  static class LineScanner extends Scanner {
    private StringTokenizer st;

    public LineScanner(String input) {
      st = new StringTokenizer(input);
    }

    @Override
    public String next() {
      return st.hasMoreTokens() ? st.nextToken() : null;
    }

    @Override
    public String nextLine() {
      throw new RuntimeException("not supported");
    }

    public boolean hasNext() {
      return st.hasMoreTokens();
    }

    private final ArrayList<Object> temp = new ArrayList<Object>();

    private void fillTemp() {
      while (st.hasMoreTokens()) {
        temp.add(st.nextToken());
      }
    }

    public String[] asStringArray() {
      fillTemp();
      String[] answer = new String[temp.size()];
      for (int i = 0; i < answer.length; i++) {
        answer[i] = (String) temp.get(i);
      }
      temp.clear();
      return answer;
    }

    public int[] asIntArray() {
      fillTemp();
      int[] answer = new int[temp.size()];
      for (int i = 0; i < answer.length; i++) {
        answer[i] = Integer.parseInt((String) temp.get(i));
      }
      temp.clear();
      return answer;
    }

    public long[] asLongArray() {
      fillTemp();
      long[] answer = new long[temp.size()];
      for (int i = 0; i < answer.length; i++) {
        answer[i] = Long.parseLong((String) temp.get(i));
      }
      temp.clear();
      return answer;
    }

    public double[] asDoubleArray() {
      fillTemp();
      double[] answer = new double[temp.size()];
      for (int i = 0; i < answer.length; i++) {
        answer[i] = Double.parseDouble((String) temp.get(i));
      }
      temp.clear();
      return answer;
    }
  }

  static class SuperScanner extends Scanner {
    private InputStream stream;
    private byte[] buf = new byte[8096];
    private int curChar;
    private int numChars;

    public SuperScanner() {
        this.stream = System.in;
    }

    public int read() {
        if (numChars == -1)
            return -1;
        if (curChar >= numChars) {
            curChar = 0;
            try {
                numChars = stream.read(buf);
            } catch (IOException e) {
                throw new InputMismatchException();
            }
            if (numChars <= 0)
                return -1;
        }
        return buf[curChar++];
    }
    
    public static boolean isWhitespace(int c) {
      return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
    }

    public static boolean isLineEnd(int c) {
      return c == '\n' || c == -1;
    }
    
    private final StringBuilder sb = new StringBuilder();
    
    @Override
    public String next() {
      int c = read();
      while (isWhitespace(c)) {
          if (c == -1) {
            return null;
          }
          c = read();
      }
      sb.setLength(0);
      do {
          sb.append((char) c);
          c = read();
      } while (!isWhitespace(c));
      return sb.toString();
    }

    @Override
    public String nextLine() {
      sb.setLength(0);
      int c;
      while (true) {
        c = read();
        if (!isLineEnd(c)) {
          sb.append((char) c);
        } else {
          break;
        }
      }
      if (c == -1 && sb.length() == 0) {
        return null;
      } else {
        if (sb.length() > 0 && sb.charAt(sb.length() - 1) == '\r') {
          return sb.substring(0, sb.length() - 1);
        } else {
          return sb.toString();
        }
      }
    }

    public LineScanner nextLineScanner() {
      String line = nextLine();
      if (line == null) {
        return null;
      } else {
        return new LineScanner(line);
      }
    }

    public LineScanner nextNonEmptyLineScanner() {
      while (true) {
        String line = nextLine();
        if (line == null) {
          return null;
        } else if (!line.isEmpty()) {
          return new LineScanner(line);
        }
      }
    }

    @Override
    public int nextInt() {
        int c = read();
        while (isWhitespace(c)) {
            c = read();
        }
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        }
        int res = 0;
        do {
            if (c < '0' || c > '9')
                throw new InputMismatchException();
            res = (res << 3) + (res << 1);
            res += c - '0';
            c = read();
        } while (!isWhitespace(c));
        return res * sgn;
    }

    @Override
    public long nextLong() {
        int c = read();
        while (isWhitespace(c))
            c = read();
        int sgn = 1;
        if (c == '-') {
            sgn = -1;
            c = read();
        }
        long res = 0;
        do {
            if (c < '0' || c > '9')
                throw new InputMismatchException();
            res = (res << 3) + (res << 1);
            res += c - '0';
            c = read();
        } while (!isWhitespace(c));
        return res * sgn;
    }
  }
  
  static abstract class Scanner {

    public abstract String next();

    public abstract String nextLine();

    public int nextIntOrQuit() {
      Integer n = nextInteger();
      if (n == null) {
        sw.close();
        System.exit(0);
      }
      return n.intValue();
    }

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

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

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

    public int[] nextIntArray(int n) {
      int[] res = new int[n];
      for (int i = 0; i < res.length; i++)
        res[i] = nextInt();
      return res;
    }

    public long[] nextLongArray(int n) {
      long[] res = new long[n];
      for (int i = 0; i < res.length; i++)
        res[i] = nextLong();
      return res;
    }

    public double[] nextDoubleArray(int n) {
      double[] res = new double[n];
      for (int i = 0; i < res.length; i++)
        res[i] = nextDouble();
      return res;
    }

    public void sortIntArray(int[] array) {
      Integer[] vals = new Integer[array.length];
      for (int i = 0; i < array.length; i++)
        vals[i] = array[i];
      Arrays.sort(vals);
      for (int i = 0; i < array.length; i++)
        array[i] = vals[i];
    }

    public void sortLongArray(long[] array) {
      Long[] vals = new Long[array.length];
      for (int i = 0; i < array.length; i++)
        vals[i] = array[i];
      Arrays.sort(vals);
      for (int i = 0; i < array.length; i++)
        array[i] = vals[i];
    }

    public void sortDoubleArray(double[] array) {
      Double[] vals = new Double[array.length];
      for (int i = 0; i < array.length; i++)
        vals[i] = array[i];
      Arrays.sort(vals);
      for (int i = 0; i < array.length; i++)
        array[i] = vals[i];
    }

    public String[] nextStringArray(int n) {
      String[] vals = new String[n];
      for (int i = 0; i < n; i++)
        vals[i] = next();
      return vals;
    }

    public Integer nextInteger() {
      String s = next();
      if (s == null)
        return null;
      return Integer.parseInt(s);
    }

    public int[][] nextIntMatrix(int n, int m) {
      int[][] ans = new int[n][];
      for (int i = 0; i < n; i++)
        ans[i] = nextIntArray(m);
      return ans;
    }

    public char[][] nextGrid(int r) {
      char[][] grid = new char[r][];
      for (int i = 0; i < r; i++)
        grid[i] = next().toCharArray();
      return grid;
    }

    public static <T> T fill(T arreglo, int val) {
      if (arreglo instanceof Object[]) {
        Object[] a = (Object[]) arreglo;
        for (Object x : a)
          fill(x, val);
      } else if (arreglo instanceof int[])
        Arrays.fill((int[]) arreglo, val);
      else if (arreglo instanceof double[])
        Arrays.fill((double[]) arreglo, val);
      else if (arreglo instanceof long[])
        Arrays.fill((long[]) arreglo, val);
      return arreglo;
    }

    public <T> T[] nextObjectArray(Class<T> clazz, int size) {
      @SuppressWarnings("unchecked")
      T[] result = (T[]) java.lang.reflect.Array.newInstance(clazz, size);
      for (int c = 0; c < 3; c++) {
        Constructor<T> constructor;
        try {
          if (c == 0)
            constructor = clazz.getDeclaredConstructor(Scanner.class,
                Integer.TYPE);
          else if (c == 1)
            constructor = clazz.getDeclaredConstructor(Scanner.class);
          else
            constructor = clazz.getDeclaredConstructor();
        } catch (Exception e) {
          continue;
        }
        try {
          for (int i = 0; i < result.length; i++) {
            if (c == 0)
              result[i] = constructor.newInstance(this, i);
            else if (c == 1)
              result[i] = constructor.newInstance(this);
            else
              result[i] = constructor.newInstance();
          }
        } catch (Exception e) {
          throw new RuntimeException(e);
        }
        return result;
      }
      throw new RuntimeException("Constructor not found");
    }

    public Collection<Integer> wrap(int[] as) {
      ArrayList<Integer> ans = new ArrayList<Integer>();
      for (int i : as)
        ans.add(i);
      return ans;
    }

    public int[] unwrap(Collection<Integer> collection) {
      int[] vals = new int[collection.size()];
      int index = 0;
      for (int i : collection)
        vals[index++] = i;
      return vals;
    }

    int testCases = Integer.MIN_VALUE;

    boolean testCases() {
      if (testCases == Integer.MIN_VALUE) {
        testCases = nextInt();
      }
      return --testCases >= 0;
    }
  }

  static class SuperWriter {

    private final PrintWriter writer;

    public SuperWriter(OutputStream outputStream) {
      writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
    }

    public SuperWriter(Writer writer) {
        this.writer = new PrintWriter(writer);
    }

    public void close() {
        writer.flush();
        writer.close();
    }

    public void printLine(String line) {
      writer.println(line);
      if (!SHOULD_BUFFER_OUTPUT) {
        writer.flush();
      }
    }

    public void printLine(int... vals) {
      if (vals.length == 0) {
        writer.println();
      } else {
        writer.print(vals[0]);
        for (int i = 1; i < vals.length; i++)
          writer.print(" ".concat(String.valueOf(vals[i])));
        writer.println();
      }
      if (!SHOULD_BUFFER_OUTPUT) {
        writer.flush();
      }
    }

    public void printLine(long... vals) {
      if (vals.length == 0) {
        writer.println();
      } else {
        writer.print(vals[0]);
        for (int i = 1; i < vals.length; i++)
          writer.print(" ".concat(String.valueOf(vals[i])));
        writer.println();
      }
      if (!SHOULD_BUFFER_OUTPUT) {
        writer.flush();
      }
    }

    public void printLine(double... vals) {
      if (vals.length == 0) {
        writer.println();
      } else {
        writer.print(vals[0]);
        for (int i = 1; i < vals.length; i++)
          writer.print(" ".concat(String.valueOf(vals[i])));
        writer.println();
      }
      if (!SHOULD_BUFFER_OUTPUT) {
        writer.flush();
      }
    }

    public void printLine(int prec, double... vals) {
      if (vals.length == 0) {
        writer.println();
      } else {
        String precision = "%." + prec + "f";
        writer.print(String.format(precision, vals[0]).replace(',', '.'));
        precision = " " + precision;
        for (int i = 1; i < vals.length; i++)
          writer.print(String.format(precision, vals[i]).replace(',', '.'));
        writer.println();
      }
      if (!SHOULD_BUFFER_OUTPUT) {
        writer.flush();
      }
    }

    public <E> void printLine(Collection<E> vals) {
      if (vals.size() == 0) {
        writer.println();
      } else {
        int i = 0;
        for (E val : vals) {
          if (i++ == 0) {
            writer.print(val.toString());
          } else {
            writer.print(" ".concat(val.toString()));
          }
        }
        writer.println();
      }
      if (!SHOULD_BUFFER_OUTPUT) {
        writer.flush();
      }
    }

    public void printSimple(String value) {
      writer.print(value);
      if (!SHOULD_BUFFER_OUTPUT) {
        writer.flush();
      }
    }

    public boolean ifZeroExit(Number... values) {
    	for (Number number : values) {
    		if (number.doubleValue() != 0.0d || number.longValue() != 0) {
    			return false;
    		}
    	}
    	close();
    	System.exit(0);
    	return true;
    }
  }


  public static void main(String[] args) {
    main();
    sw.close();
  }
}
