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.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.StringTokenizer;


public class hello2
 {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 String sum (String s)
    {
        String s1 = ""; 
        
        if(s.contains("a"))
            s1+="a";
        if(s.contains("e"))
            s1+="e";
        if(s.contains("i"))
            s1+="i";
        if(s.contains("o"))
            s1+="o";
        if(s.contains("u"))
            s1+="u";
        
            return s1;
            
        
    }
    

    public static HashMap<String, Integer> sortByValue(HashMap<String, Integer> hm) 
    { 
        // Create a list from elements of HashMap 
        List<Map.Entry<String, Integer> > list = 
               new LinkedList<Map.Entry<String, Integer> >(hm.entrySet()); 
  
        // Sort the list 
        Collections.sort(list, new Comparator<Map.Entry<String, Integer> >() { 
            public int compare(Map.Entry<String, Integer> o1,  
                               Map.Entry<String, Integer> o2) 
            { 
                return (o1.getValue()).compareTo(o2.getValue()); 
            } 
        }); 
          
        // put data from sorted list to hashmap  
        HashMap<String, Integer> temp = new LinkedHashMap<String, Integer>(); 
        for (Map.Entry<String, Integer> aa : list) { 
            temp.put(aa.getKey(), aa.getValue()); 
        } 
        return temp; 
    } 
    
    
public static void main(String args[])
    {
        FastReader input =new FastReader();
      
        
        
       
        	int n = input.nextInt();
            
        	boolean[] vis = new boolean[n + 1];
            
        	int[] a = new int[n + 1];
            
        	for (int i = 1; i <= n; i++) 
        		vis[a[i] = input.nextInt()] = true;
            
        	
        	ArrayList<Integer> not = new ArrayList<>();
            
        	for (int i = 1; i <= n; i++) {
                if (!vis[i]) not.add(i);
            }
            
        	int ptr = 0;
            
        	for (int i = 1; i <= n; i++) {
                if (a[i] == a[i - 1]) System.out.print(not.get(ptr++) + " ");
                else System.out.print(a[i - 1] + " ");
            }
        		
        		
        }
        	  

public static boolean range(int x,int y,int n,int m)
{
	if(x<0 || x>n-1 || y<0 || y>m-1)
		return false;
	
	
	return true;
}
   
public static int even_element(int b[],int n)
{
	int c[] = new int[n/2 + 1];
	int l=0;
	for(int i=1;i<n;i+=2)
	{
		c[l] = b[i];
		
		System.out.print(c[l] + " ");
		l++;
	}
	System.out.println();
	if(c.length!=1)
	{
		return even_element(c,n/2);
	}
	else
		return c[0];
}

      
       	
        	
        	
 
    
    static boolean isPrime(int n) 
    { 
        // Corner case 
        if (n <= 1) 
            return false; 
  
        // Check from 2 to n-1 
        for (int i = 2; i < n; i++) 
            if (n % i == 0) 
                return false; 
  
        return true; 
    } 
 }
 
 
 class Pair
 {
     int a;
     int b;
     Pair(int a,int b)
     {
         this.a=a;
         this.b=b;
     }
 }
 