#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <cmath>
#include <iostream>
#include <queue>
#include <list>
#include <map>
#include <numeric>
#include <set>
#include <sstream>
#include <string>
#include <vector>
using namespace std;
#define REP(i,a,n) for(int i=(a); i<(int)(n); i++)
#define rep(i,n) REP(i,0,n)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it)
#define ALLOF(c) (c).begin(), (c).end()
typedef long long ll;

#define MAX_V 110
int V;
vector<int> G[MAX_V];
int match[MAX_V];
bool used[MAX_V];

void init_graph(){
  for(int i=0; i<MAX_V; i++){
    G[i].clear();
    match[i] = -1;
    used[i] = false;
  }
}
void add_edge(int u, int v){
  G[u].push_back(v);
  G[v].push_back(u);
}
bool dfs(int v){
  used[v] = true;
  for(int i=0; i<G[v].size(); i++){
    int u = G[v][i], w = match[u];
    if(w<0||!used[w]&&dfs(w)){
      match[v] = u;
      match[u] = v;
      return true;
    }
  }
  return false;
}
int bipartite_matching(){
  int res = 0;
  rep(i,MAX_V) match[i] = -1;
  for(int v=0; v<V; v++){
    if(match[v] < 0){
      rep(i,MAX_V) used[i] = false;
      if(dfs(v)){
        res++;
      }
    }
  }
  return res;
}

int main(){
  int N;
  cin >> N;
  vector<int> v;
  rep(i,N){
    int tmp;
    cin >> tmp;
    v.push_back(tmp);
  }
  init_graph();
  V = 2*N;
  
  rep(i,N){
    rep(j,N){
      if(j==v[i]) continue;
      add_edge(i, N+j);
    }
  }

  int res = bipartite_matching();
  if(res != N){
    cout << -1 << endl;
    return 0;
  }

  rep(i,N){
    cout << match[i]-N << endl;
  }
  
  
  return 0;
}