#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <string>
#include <map>
#include <set>
#include <stack>
#include <tuple>
#include <deque>
#include <array>
#include <numeric>
#include <bitset>
#include <iomanip>
#include <cassert>
#include <chrono>
#include <random>
#include <limits>
#include <iterator>
#include <functional>
#include <sstream>
#include <fstream>
#include <complex>
#include <cstring>
#include <unordered_map>
#include <unordered_set>
using namespace std;

using ll = long long;
constexpr int INF = 1001001001;
constexpr int mod = 1000000007;
// constexpr int mod = 998244353;

template<class T>
inline bool chmax(T& x, T y){
    if(x < y){
        x = y;
        return true;
    }
    return false;
}
template<class T>
inline bool chmin(T& x, T y){
    if(x > y){
        x = y;
        return true;
    }
    return false;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int N;
    cin >> N;
    vector<int> A(N);
    for(int i = 0; i < N; ++i)  cin >> A[i];

    if(N == 1 && A[0] == 0){
        cout << -1 << endl;
        return 0;
    }
    if(N > 1){
        bool ng = true;
        for(int i = 0; i + 1 < N; ++i){
            if(A[i] != A[i + 1])    ng = false;
        }
        if(ng && 0 <= A[0] && A[0] < N){
            cout << -1 << endl;
            return 0;
        }
    }

    vector<int> S(N);
    for(int i = 0; i < N; ++i)  S[i] = i;
    bool update = true;
    while(update){
        update = false;
        for(int i = 0; i < N; ++i){
            if(S[i] == A[i]){
                for(int j = 0; j < N; ++j){
                    if(i == j)  continue;
                    if(S[j] != A[i] && S[i] != A[j]){
                        swap(S[i], S[j]);
                        update = true;
                        break;
                    }
                }
                break;
            }
        }
    }

    for(int i = 0; i < N; ++i)  cout << S[i] << '\n';

    return 0;
}