Problem: You are given an array of n elements, you must make it a co-prime array in as few moves as possible.

In each move you can insert any positive integral number you want not greater than 109 in any place in the array.

An array is co-prime if any two adjacent numbers of it are co-prime.

In the number theory, two integers a and b are said to be co-prime if the only positive integer that divides both of them is 1.

Input

The first line contains integer n (1 ≤ n ≤ 1000) — the number of elements in the given array.

The second line contains n integers ai (1 ≤ ai ≤ 109) — the elements of the array a.

Output

Print integer k on the first line — the least number of elements needed to add to the array a to make it co-prime.

The second line should contain n + k integers aj — the elements of the array a after adding k elements to it. Note that the new array should be co-prime, so any two adjacent values should be co-prime. Also the new array should be got from the original array a by adding k elements to it.

If there are multiple answers you can print any one of them.

Example

Input

3
2 7 28


Output

1
2 7 9 28

Solution (in JAVA):

Solution:
//package cf;
import java.io.*;
import java.util.*;

public final class Cf {
    static int a[];
    public static void main(String[] args) throws Exception {
        BufferedWriter out = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(java.io.FileDescriptor.out), "ASCII"), 512);        
        FastReader sc = new FastReader();
        int tc=1,n;
        ArrayList<Integer>ans;
        while(tc-->0)
        {  
           n=sc.nextInt();
           ans=new ArrayList<>();
           a=new int[n];
           for(int i=0;i<n;i++)
           {
               a[i]=sc.nextInt();
           }
           ans.add(a[0]);
           for(int i=1;i<n;i++)
           {
               if(go(a[i],a[i-1])!=1)ans.add(1);
               ans.add(a[i]);
           }
         out.write((ans.size()-n)+"\n");
         for(int v:ans)out.write(v+" ");
         
        out.flush();
        
       }
        
        
        
    }

  public static int go(int a,int b)
  {
      if(a==0)return b;
      return go(b%a,a);
  }
    
    
    public static void debug(String s)
    {
        System.out.println(s);
    }

    ///////////////////////////////////////////////////////////////////////////////////
    //////////////////////////////////////////////////////////////////////////////////////////////
    static class FastReader {        
        
        BufferedReader br;        
        StringTokenizer st;        
        
        public FastReader() {            
            br = new BufferedReader(new InputStreamReader(System.in));            
        }        
        
        String next() {            
            while (st == null || !st.hasMoreElements()) {                
                try {                    
                    st = new StringTokenizer(br.readLine());                    
                } catch (IOException e) {                    
                    e.printStackTrace();                    
                }                
            }            
            return st.nextToken();            
        }        
        
        int nextInt() {            
            return Integer.parseInt(next());            
        }        
        
        long nextLong() {            
            return Long.parseLong(next());            
        }        
        
        double nextDouble() {            
            return Double.parseDouble(next());            
        }        
        
        String nextLine() {            
            String str = "";            
            try {                
                str = br.readLine();                
            } catch (IOException e) {                
                e.printStackTrace();                
            }            
            return str;            
        }        
    }
    //////////////////////////////////////////////////////////////////

    static class Reader {        

        final private int BUFFER_SIZE = 1 << 16;        
        private DataInputStream din;        
        private byte[] buffer;        
        private int bufferPointer, bytesRead;        
        
        public Reader() {            
            din = new DataInputStream(System.in);            
            buffer = new byte[BUFFER_SIZE];            
            bufferPointer = bytesRead = 0;            
        }        
        
        public Reader(String file_name) throws IOException {            
            din = new DataInputStream(new FileInputStream(file_name));            
            buffer = new byte[BUFFER_SIZE];            
            bufferPointer = bytesRead = 0;            
        }        
        
        public String readLine() throws IOException {            
            byte[] buf = new byte[1002]; // line length 
            int cnt = 0, c;            
            while ((c = read()) != -1) {                
                if (c == '\n') {
                    break;
                }                
                buf[cnt++] = (byte) c;                
            }            
            return new String(buf, 0, cnt);            
        }        
        
        public int nextInt() throws IOException {            
            int ret = 0;            
            byte c = read();            
            while (c <= ' ') {
                c = read();
            }            
            boolean neg = (c == '-');            
            if (neg) {
                c = read();
            }            
            do {                
                ret = ret * 10 + c - '0';                
            } while ((c = read()) >= '0' && c <= '9');            
            
            if (neg) {
                return -ret;
            }            
            return ret;            
        }        
        
        public long nextLong() throws IOException {            
            long ret = 0;            
            byte c = read();            
            while (c <= ' ') {
                c = read();
            }            
            boolean neg = (c == '-');            
            if (neg) {
                c = read();
            }            
            do {                
                ret = ret * 10 + c - '0';                
            } while ((c = read()) >= '0' && c <= '9');            
            if (neg) {
                return -ret;
            }            
            return ret;            
        }        
        
        public double nextDouble() throws IOException {            
            double ret = 0, div = 1;            
            byte c = read();            
            while (c <= ' ') {
                c = read();
            }            
            boolean neg = (c == '-');            
            if (neg) {
                c = read();
            }            
            
            do {                
                ret = ret * 10 + c - '0';                
            } while ((c = read()) >= '0' && c <= '9');            
            
            if (c == '.') {                
                while ((c = read()) >= '0' && c <= '9') {                    
                    ret += (c - '0') / (div *= 10);                    
                }                
            }            
            
            if (neg) {
                return -ret;
            }            
            return ret;            
        }        
        
        private void fillBuffer() throws IOException {            
            bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);            
            if (bytesRead == -1) {
                buffer[0] = -1;
            }            
        }        
        
        private byte read() throws IOException {            
            if (bufferPointer == bytesRead) {
                fillBuffer();
            }            
            return buffer[bufferPointer++];            
        }        
        
        public void close() throws IOException {            
            if (din == null) {
                return;
            }            
            din.close();            
        }        
    }    
}