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 math 
import sys

sys.setrecursionlimit(10**4) 

def Divisors(n) : 
	
	l=[]
	i = 1
	while i <= math.sqrt(n): 
		
		if (n % i == 0) : 
			
			
			if (n // i == i) : 
				l.append(i)
			else : 
				l.append(i)
				l.append(n//i)
		i = i + 1
	return l

def SieveOfEratosthenes(n): 
	
	l=[]
	
	prime = [True for i in range(n+1)] 
	p = 2
	while (p * p <= n): 
		
		if (prime[p] == True): 
			
			for i in range(p * p, n+1, p): 
				prime[i] = False
		p += 1
	
	for p in range(2, n+1): 
		if prime[p]: 
			l.append(p)
	
	return l		

def primeFactors(n): 
	
	l=[]
	
	while n % 2 == 0: 
		l.append(2) 
		n = n / 2
		
	for i in range(3,int(math.sqrt(n))+1,2): 
		
		while n % i== 0: 
			l.append(i) 
			n = n / i 
			
	if n > 2: 
		l.append(n)
	
	return(l)	
		

def Factors(n) : 
	
	
	result = []
	
	for i in range(2,(int)(math.sqrt(n))+1) : 

		if (n % i == 0) : 
		    
			if (i == (n/i)) : 
				result.append(i)
			else : 
			    result.append(i)
			    result.append(n//i)
		
	result.append(1)
	result.append(n)
	return result

def maxSubArraySum(a): 
	
	max_so_far = 0
	max_ending_here = 0
	size=len(a)
	
	for i in range(0, size): 
		max_ending_here = max_ending_here + a[i] 
		if (max_so_far < max_ending_here): 
			max_so_far = max_ending_here 

		if max_ending_here < 0: 
			max_ending_here = 0
	return max_so_far 

#print(SieveOfEratosthenes(100))
#print(Divisors(100))
#print(primeFactors(100))
#print(Factors(100))
#print(maxSubArraySum(a)
def longestsubarray(arr, n, k): 
    current_count = 0
      
    # this will contain length of  
    # longest subarray found 
    max_count = 0
  
    for i in range(0, n, 1): 
        if (arr[i] % k != 0): 
            current_count += 1
        else: 
            current_count = 0
        max_count = max(current_count,  
                            max_count) 
      
    return max_count 
def main():

    n=int(input())
    l=list(map(int,input().split()))
    
    l1=[]
    
    for j in range(0,n):
        l1.append(-1)
        
    f=[]
    
    for j in range(0,1000000):
        f.append(-1)
        
    for j in range(1,n):
        if l[j-1]!=l[j]:
            l1[j]=l[j-1]
            f[l[j-1]]=1
            f[l[j]]=1
    k=0        
    for j in range(0,n): 
        if l1[j]==-1:
            while k<=1000000:
                if f[k]==-1:
                    f[k]=1
                    l1[j]=k
                    break
                k+=1
    print(*l1)            
        
            
        
                    
    
t=1
for i in range(0,t):
    main()


    