Problem: Piegirl is buying stickers for a project. Stickers come on sheets, and each sheet of stickers contains exactly n stickers. Each sticker has exactly one character printed on it, so a sheet of stickers can be described by a string of length n. Piegirl wants to create a string s using stickers. She may buy as many sheets of stickers as she wants, and may specify any string of length n for the sheets, but all the sheets must be identical, so the string is the same for all sheets. Once she attains the sheets of stickers, she will take some of the stickers from the sheets and arrange (in any order) them to form s. Determine the minimum number of sheets she has to buy, and provide a string describing a possible sheet of stickers she should buy.

Input

The first line contains string s (1 ≤ |s| ≤ 1000), consisting of lowercase English characters only. The second line contains an integer n (1 ≤ n ≤ 1000).

Output

On the first line, print the minimum number of sheets Piegirl has to buy. On the second line, print a string consisting of n lower case English characters. This string should describe a sheet of stickers that Piegirl can buy in order to minimize the number of sheets. If Piegirl cannot possibly form the string s, print instead a single line with the number -1.

Examples

Input

banana
4


Output

2
baan


Input

banana
3


Output

3
nab


Input

banana
2


Output

-1

Note

In the second example, Piegirl can order 3 sheets of stickers with the characters "nab". She can take characters "nab" from the first sheet, "na" from the second, and "a" from the third, and arrange them to from "banana".

Solution (in JAVA):

Solution:
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.util.Arrays;
import java.io.BufferedWriter;
import java.util.InputMismatchException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.NoSuchElementException;
import java.io.Writer;
import java.math.BigInteger;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 * @author Egor Kulikov (egor@egork.net)
 */
public class Main {
	public static void main(String[] args) {
		InputStream inputStream = System.in;
		OutputStream outputStream = System.out;
		InputReader in = new InputReader(inputStream);
		OutputWriter out = new OutputWriter(outputStream);
		TaskA solver = new TaskA();
		solver.solve(1, in, out);
		out.close();
	}
}

class TaskA {
    public void solve(int testNumber, InputReader in, OutputWriter out) {
		char[] required = in.readString().toCharArray();
		int length = in.readInt();
		final int[] qty = new int[26];
		for (char c : required)
			qty[c - 'a']++;
		final int[] taken = new int[26];
		Heap heap = new Heap(new IntComparator() {
			public int compare(int first, int second) {
				return taken[first] * qty[second] - qty[first] * taken[second];
			}
		}, 26);
		for (int i = 0; i < 26; i++) {
			if (qty[i] != 0)
				heap.add(i);
		}
		if (length < heap.getSize()) {
			out.printLine(-1);
			return;
		}
		StringBuilder answer = new StringBuilder(length);
		for (int i = 0; i < length; i++) {
			int current = heap.poll();
			answer.append((char)('a' + current));
			taken[current]++;
			heap.add(current);
		}
		int max = 0;
		for (int i = 0; i < 26; i++) {
			if (qty[i] != 0)
				max = Math.max(max, (qty[i] - 1) / taken[i] + 1);
		}
		out.printLine(max);
		out.printLine(answer);
    }
}

class InputReader {

	private InputStream stream;
	private byte[] buf = new byte[1024];
	private int curChar;
	private int numChars;
	private SpaceCharFilter filter;

	public InputReader(InputStream stream) {
		this.stream = stream;
	}

	public int read() {
		if (numChars == -1)
			throw new InputMismatchException();
		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 int readInt() {
		int c = read();
		while (isSpaceChar(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 *= 10;
			res += c - '0';
			c = read();
		} while (!isSpaceChar(c));
		return res * sgn;
	}

	public String readString() {
		int c = read();
		while (isSpaceChar(c))
			c = read();
		StringBuilder res = new StringBuilder();
		do {
			res.appendCodePoint(c);
			c = read();
		} while (!isSpaceChar(c));
		return res.toString();
	}

	public boolean isSpaceChar(int c) {
		if (filter != null)
			return filter.isSpaceChar(c);
		return isWhitespace(c);
	}

	public static boolean isWhitespace(int c) {
		return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
	}

	public interface SpaceCharFilter {
		public boolean isSpaceChar(int ch);
	}
}

class OutputWriter {
	private final PrintWriter writer;

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

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

	public void print(Object...objects) {
		for (int i = 0; i < objects.length; i++) {
			if (i != 0)
				writer.print(' ');
			writer.print(objects[i]);
		}
	}

    public void printLine(Object...objects) {
		print(objects);
		writer.println();
	}

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

	}

class Heap {
	private IntComparator comparator;
	private int size = 0;
	private int[] elements;
	private int[] at;

	public Heap(int maxElement) {
		this(10, maxElement);
	}

	public Heap(IntComparator comparator, int maxElement) {
		this(10, comparator, maxElement);
	}

	public Heap(int capacity, int maxElement) {
		this(capacity, IntComparator.DEFAULT, maxElement);
	}

	public Heap(int capacity, IntComparator comparator, int maxElement) {
		this.comparator = comparator;
		elements = new int[capacity];
		at = new int[maxElement];
		Arrays.fill(at, -1);
	}

	public int getSize() {
		return size;
	}

    public boolean isEmpty() {
		return size == 0;
	}

	public int add(int element) {
		ensureCapacity(size + 1);
		elements[size] = element;
		at[element] = size;
		shiftUp(size++);
		return at[element];
	}

	public void shiftUp(int index) {
//		if (index < 0 || index >= size)
//			throw new IllegalArgumentException();
		int value = elements[index];
		while (index != 0) {
			int parent = (index - 1) >>> 1;
			int parentValue = elements[parent];
			if (comparator.compare(parentValue, value) <= 0) {
				elements[index] = value;
				at[value] = index;
				return;
			}
			elements[index] = parentValue;
			at[parentValue] = index;
			index = parent;
		}
		elements[0] = value;
		at[value] = 0;
	}

	public void shiftDown(int index) {
		if (index < 0 || index >= size)
			throw new IllegalArgumentException();
		while (true) {
			int child = (index << 1) + 1;
			if (child >= size)
				return;
			if (child + 1 < size && comparator.compare(elements[child], elements[child + 1]) > 0)
				child++;
			if (comparator.compare(elements[index], elements[child]) <= 0)
				return;
			swap(index, child);
			index = child;
		}
	}

	private void swap(int first, int second) {
		int temp = elements[first];
		elements[first] = elements[second];
		elements[second] = temp;
		at[elements[first]] = first;
		at[elements[second]] = second;
	}

	private void ensureCapacity(int size) {
		if (elements.length < size) {
			int[] oldElements = elements;
			elements = new int[Math.max(2 * elements.length, size)];
			System.arraycopy(oldElements, 0, elements, 0, this.size);
		}
	}

	public int poll() {
		if (isEmpty())
			throw new IndexOutOfBoundsException();
		int result = elements[0];
		at[result] = -1;
		if (size == 1) {
			size = 0;
			return result;
		}
		elements[0] = elements[--size];
		at[elements[0]] = 0;
		shiftDown(0);
		return result;
	}

    }

interface IntComparator {
    public static final IntComparator DEFAULT = new IntComparator() {
        public int compare(int first, int second) {
            if (first < second)
                return -1;
            if (first > second)
                return 1;
            return 0;
        }
    };

	public int compare(int first, int second);
}