from itertools import permutations

def main():
    N = int(input())
    A = [int(input()) for _ in range(N)]

    for i, a in enumerate(A):
        if a >= N:
            cands = list(range(N))
            ans = [-1]*N

            for j, b in enumerate(j, A):
                if i == j:
                    continue
                if cands[-1] == b:
                    ans.append(cands.pop(-2))
                else:
                    ans.append(cands.pop())
            ans[i] = cands.pop()
            return ans


    for a, b in zip(A, A[1:]):
        if a != b:
            break
    else: # 全て同じ番号なら
        return [-1]

    if N == 1:
        return [0]
    elif N == 2:
        if A[0] == 0:
            return [1, 0]
        else:
            return [0, 1]
    

    idx = [0]
    for i, a in enumerate(A):
        if not i:
            continue
        if a != A[0]:
            idx.append(i)
            break
    for i in range(N):
        if i not in idx:
            idx.append(i)
            break
    
    ans = [-1]*N
    cands = list(range(N))
    for i in range(N):
        if i in idx:
            continue
        if cands[-1] == A[i]:
            ans[i] = cands.pop(-2)
        else:
            ans[i] = cands.pop()
    for s in permutations(idx):
        for i in range(3):
            if A[s[i]] == cands[i]:
                break
        else:
            for i in range(3):
                ans[s[i]] = cands[i]
            return ans

print(*main(), sep="\n")