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.
// package june2020;

import java.util.*;
import java.lang.*;
import java.math.*;
import java.io.*;

public class cf_subs {
	static FastReader scn = new FastReader();
	static OutputStream out = new BufferedOutputStream(System.out);
	public static void main(String[] args) throws IOException {
		// TODO Auto-generated method stub
		int t = 1;
		while(t-->0) {
			int n = scn.nextInt();
			int[] a= new int[n];
			TreeSet<Integer> s = new TreeSet<>();
			for(int i=0;i<100005;i++) {
				s.add(i);
			}
			for(int i=0;i<n;i++) {
				a[i] = scn.nextInt();
				s.remove(a[i]);
			}
			
			int[] b = new int[n];
			Arrays.fill(b, -1);
			for(int i=1;i<n;i++) {
				if(a[i]!=a[i-1]) {
					b[i]=a[i-1];
				}
			}
			for(int i=0;i<n;i++) {
				if(b[i]!=-1) {
					continue;
				}
				b[i]=s.pollFirst();
			}
			for(int i=0;i<n;i++) {
				out.write((b[i]+" ").getBytes());
			}
			out.write("\n".getBytes());
		}
		out.close();
	}
	static int sum(int[] bits) {
		int ans=0;
		for(int i=0;i<=20;i++) {
			ans+=bits[i];
		}
		
		return ans;
	}
	public static int[] merge(int[] one,int[] two){
		int[] res = new int[one.length+two.length];
		int i = 0;
		int j = 0;
		int k = 0;
		
		while(i<one.length&&j<two.length){
			if(one[i]<two[j]){
				res[k] = one[i];
				i++;
				k++;
			}
			else{
				res[k] = two[j];
				j++;
				k++;
			}
		}
		
		if(i==one.length){
			while(j<two.length){
				res[k] = two[j];
				j++;
				k++;
			}
		}
		else{
			while(i<one.length){
				res[k] = one[i];
				k++;
				i++;
			}
		}
		return res;
	}
	public static int[] mergesort(int[] arr, int l, int r){
		if(l==r){
			int[] br = new int[1];
			br[0] = arr[l];
			return br;
		}
		int mid = (l+r)/2;
		int[] fh = mergesort(arr,l,mid);
		int[] sh = mergesort(arr,mid+1,r);
		
		return merge(fh,sh);
	}
//	static int dfs(int idx) {
//		
//	}
	static <T> int upperBound(List<T> ls, T x) throws RuntimeException {
		if (ls.size() == 0)
			return -1;
		if (ls.get(0) instanceof Integer) {
			return ~Collections.binarySearch(ls, x, (t1, t2) -> ((Integer) t1).compareTo((Integer) t2) > 0 ? 1 : -1);
		} else if (ls.get(0) instanceof Long) {
			return ~Collections.binarySearch(ls, x, (t1, t2) -> ((Long) t1).compareTo((Long) t2) > 0 ? 1 : -1);
		} else if (ls.get(0) instanceof Double) {
			return ~Collections.binarySearch(ls, x, (t1, t2) -> ((Double) t1).compareTo((Double) t2) > 0 ? 1 : -1);
		} else {
			System.err.println(
					String.format("%s:Arey Maa chudi padi hai", Thread.currentThread().getStackTrace()[1].getMethodName()));
			throw new RuntimeException();
		}
	}
	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; 
        } 
    }

}
