Given an array a of length n, find another array, b, of length n such that:

  * for each i (1 ≤ i ≤ n) MEX(\\{b_1, b_2, …, b_i\})=a_i. 



The MEX of a set of integers is the smallest non-negative integer that doesn't belong to this set.

If such array doesn't exist, determine this.

Input

The first line contains an integer n (1 ≤ n ≤ 10^5) — the length of the array a.

The second line contains n integers a_1, a_2, …, a_n (0 ≤ a_i ≤ i) — the elements of the array a. It's guaranteed that a_i ≤ a_{i+1} for 1≤ i < n.

Output

If there's no such array, print a single line containing -1.

Otherwise, print a single line containing n integers b_1, b_2, …, b_n (0 ≤ b_i ≤ 10^6)

If there are multiple answers, print any.

Examples

Input


3
1 2 3


Output


0 1 2 

Input


4
0 0 0 2


Output


1 3 4 0 

Input


3
1 1 3


Output


0 2 1 

Note

In the second test case, other answers like [1,1,1,0], for example, are valid.
import java.util.*;
import java.util.Scanner;
import java.io.*;
import javax.lang.model.util.ElementScanner6; 
import static java.lang.System.out;
import java.util.Stack;
import java.util.Queue;
import java.util.LinkedList;

public class C1364
{

   
    
    public static void main(String args[])
    {  

        FastReader in=new FastReader();
        PrintWriter pr = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
        int tc=1;
     
        //tc=in.nextInt();
        testloop : while(tc-->0)
        {
            
        	int n=in.nextInt();

			int arr[]=in.readIntArray(n);
			
			LinkedHashSet<Integer> hs=new LinkedHashSet<Integer>();
			ArrayList<Integer> col=new ArrayList<>();
			
			int al[]=new int[n];
			Arrays.fill(al,-1);
		
			
			
			
			for(int i=1;i<n;i++)
			{
				if(arr[i]!=arr[i-1])
				{
					al[i]=arr[i-1];
				}
				
			}
			
			for(int i=1;i<=(int)(2e5);i++)
			{
				hs.add(i);
			}
			
			for(int i=0;i<n;i++)
			{
				if(hs.contains(arr[i]))
				{
					hs.remove(arr[i]);
				}
			}
			
			for(int i : hs)
			{
				
				col.add(i);
			}
			
			
		
			
			int start=0;
			for(int i=0;i<n;i++)
			{
				if(al[i]==-1)
				{
					al[i]=col.get(start++);
				}
			}
			
			
		
			
			
			
			
			for(int i : al)
			{
				pr.print(i+" ");
				
			}
			
			pr.println();


        }
        pr.flush();
    }


    

    static void sort(long[] a) {
		ArrayList<Long> l = new ArrayList<>();
		for (long i : a)
			l.add(i);
		Collections.sort(l);
		for (int i = 0; i < a.length; i++)
			a[i] = l.get(i);
	}
    
    
	static void sort(int[] a) {
		ArrayList<Integer> l = new ArrayList<>();
		for (int i : a)
			l.add(i);
		Collections.sort(l);
		for (int i = 0; i < a.length; i++)
			a[i] = l.get(i);
    }

    
    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()); 
        } 
        
        int[] readIntArray(int n)
        {
		int a[]=new int[n];
		for(int i=0;i<n;i++)a[i]=nextInt();
		return a;
	}
		
	long[] readLongArray(int n)
	{
		long a[]=new long[n];
		for(int i=0;i<n;i++)a[i]=nextLong();
		return a;
	}
	
        String nextLine() 
        { 
            String str = ""; 
            try
            { 
                str = br.readLine(); 
            } 
            catch (IOException e) 
            { 
                e.printStackTrace(); 
            } 
            return str; 
        } 
    } 
}


