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.*;
import java.util.*;
 
import javax.sound.midi.Synthesizer;
public class Problem5 {
 
	static ArrayList<Integer> primes;
 
	static void sieve(int N)
	{
		boolean[] isComposite = new boolean[N];
		primes = new ArrayList<Integer>(N / 10);
		for(int i = 2; i < N; ++i)
			if(!isComposite[i])
			{
				primes.add(i);
				if(1l * i * i < N)
					for(int j = i * i; j < N; j += i)
						isComposite[j] = true;
			}
	}
 
/*	static ArrayList<Pair> primeFactors(int N)
	*{
		ArrayList<Pair> factors = new ArrayList<Pair>();
 
		int idx = 0, p = primes.get(0);
		while(1l * p * p <= N)
		{
			int e = 0;
			while(N % p == 0) 
			{ 
				N /= p; 
				++e; 
			}
			if(e != 0)
				factors.add(new Pair(p, e));
			p = primes.get(++idx);
		}
		if(N != 1)
			factors.add(new Pair(N, 1));
		return factors;
	}**/
 
	static double eps= 1e-12;
	public static void main(String[] args) throws Exception 
	{
		Scanner sc = new Scanner(System.in); 
		PrintWriter out = new PrintWriter(System.out);
		String s=sc.nextLine();
		int n=sc.nextInt();
		HashSet<Character> set=new HashSet<>();
		char c[]=s.toCharArray();
		StringBuilder sb=new StringBuilder();
		int d[]=new int[26];
		int count[]=new int[26];
		PriorityQueue<Pair> pq=new PriorityQueue<Pair>();
		TreeMap<Character,Integer> map=new TreeMap<>(); 
		for (int i = 0; i < c.length; i++) {
			count[c[i]-'a']++;
		}
		for (int i = 0; i < c.length; i++) {
			if(!set.contains(c[i])) {
				set.add(c[i]);
			sb.append(c[i]);
			d[c[i]-'a']++;
			}
			
		}
		if(set.size()>n) {
			System.out.println(-1);
			return;
		}
		n=n-set.size();
		
		char c1='a';
		
		for (int i = 0; i < count.length; i++) {
			if(count[c1-'a']>0)
			pq.add(new Pair(c1,count[c1-'a']));
			c1++;
		
		}
		
		while(!pq.isEmpty()&&n>0) {
			Pair p=pq.remove();
			sb.append(p.p);
			d[p.p-'a']++;
			
			pq.add(new Pair(p.p,(int) Math.ceil(1.0*count[p.p-'a']/d[p.p-'a']*1.0)));
			n--;
		}
		while(n>0) {
			sb.append('a');
			d[0]++;
			n--;
		}
 
		int max=1;
		for (int i = 0; i < d.length; i++) {
			for (int j = 2; j <=1000; j++) {
				if(d[i]>=count[i]) {
					break;
				}
				
				else if(d[i]*j>=count[i]) {
					
					max=Math.max(j, max);
				break;
				}
			}
		}
		System.out.println(max);
		System.out.println(sb);
		
		
		
		/**for(Map.Entry<Character,Integer> entry : map.entrySet()) {
			  char key = entry.getKey();
			  Integer value = entry.getValue();
 
		}**/
		
		
		out.flush();
		
		
	}
 
	static class Pair implements Comparable<Pair>
	{
		char p;int e;
 
		Pair(char x, int y) { p = x; e = y; }
 
		@Override
		public int compareTo(Pair o) {
			if(this.e<o.e)
			return 1;
			else
				return -1;
		}
		
 
	}
 
	static class Scanner 
	{
		StringTokenizer st;
		BufferedReader br;
 
		public Scanner(InputStream s){	br = new BufferedReader(new InputStreamReader(s));}
 
		public String next() throws IOException 
		{
			while (st == null || !st.hasMoreTokens()) 
				st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}
 
		public int nextInt() throws IOException {return Integer.parseInt(next());}
 
		public long nextLong() throws IOException {return Long.parseLong(next());}
 
		public String nextLine() throws IOException {return br.readLine();}
 
		public double nextDouble() throws IOException
		{
			String x = next();
			StringBuilder sb = new StringBuilder("0");
			double res = 0, f = 1;
			boolean dec = false, neg = false;
			int start = 0;
			if(x.charAt(0) == '-')
			{
				neg = true;
				start++;
			}
			for(int i = start; i < x.length(); i++)
				if(x.charAt(i) == '.')
				{
					res = Long.parseLong(sb.toString());
					sb = new StringBuilder("0");
					dec = true;
				}
				else
				{
					sb.append(x.charAt(i));
					if(dec)
						f *= 10;
				}
			res += Long.parseLong(sb.toString()) / f;
			return res * (neg?-1:1);
		}
 
		public boolean ready() throws IOException {return br.ready();}
 
		public boolean nextEmpty() throws IOException
		{
			String s = br.readLine();
			st = new StringTokenizer(s);
			return s.isEmpty();
		}
		public void waitForInput() throws InterruptedException {Thread.sleep(2500);}
		}
 
 
	
}