#include <bits/stdc++.h>

using namespace std;

namespace {

    typedef double real;
    typedef long long ll;

    template<class T> ostream& operator<<(ostream& os, const vector<T>& vs) {
        for (auto& v : vs) {
            os << v << endl;
        }
        return os;
    }
    template<class T> istream& operator>>(istream& is, vector<T>& vs) {
        for (auto it = vs.begin(); it != vs.end(); it++) is >> *it;
        return is;
    }

    int N;
    vector<int> A;
    void input() {
        cin >> N;
        A.clear(); A.resize(N); cin >> A;
    }

    void solve() {
        vector<bool> ng_exist(N, false);
        vector<vector<int>> ng_id(N);
        for (int i = 0; i < N; i++) {
            if (A[i] >= N) continue;
            ng_id[A[i]].push_back(i);
            ng_exist[A[i]] = true;
        }
        vector<int> wildcard;
        for (int i = 0; i < N; i++) if (not ng_exist[i]) wildcard.push_back(i);

        auto check = [&] {
            for (int i = 0; i < N; i++) {
                if (int(ng_id[i].size()) == N) return true;
            }
            return false;
        };

        if (check()) {
            int x = 0;
            for (int j = 0; j < N; j++) {
                if (ng_exist[j]) {
                    x = j;
                    break;
                }
            }
            if (x < N) {
                cout << -1 << endl;
                return;
            }
        }

        if (int(wildcard.size()) == N) {
            for (int i = 0; i < N; i++) {
                cout << i << endl;
            }
            return;
        }

        //cout << "ng_id: " << ng_id << endl;
        //cout << "wildcard: " << wildcard << endl;

        vector<int> id(N, -10);
        for (int i = 0; i < N; i++) {
            if (ng_id[i].empty()) continue;
            int x = ng_id[i][0];
            int next = (i + 1) % N;
            while (ng_id[next].empty()) {
                next = (next + 1) % N;
                if (i == next) break;
            }
            if (i == next) {
                id[x] = wildcard.back();
                wildcard.pop_back();
            } else {
                id[x] = next;
            }
            for (int j = 1; j < int(ng_id[i].size()); j++) {
                id[ng_id[i][j]] = wildcard.back();
                wildcard.pop_back();
            }
            if (i == next) {
                wildcard.push_back(i);
            }
        }
        for (int i = 0; i < N; i++) {
            if (id[i] < 0) {
                id[i] = wildcard.back();
                wildcard.pop_back();
            }
        }
        cout << id << endl;
    }
}

int main() {
    input(); solve();
    return 0;
}