#include<bits/stdc++.h>

using namespace std;

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

  int n;
  cin >> n;
  vector<int> val={(int)1e9};
  vector<int> inv(n+5);
  vector<int> l(n+5),r(n+5);
  for(int i=1;i<=n;i++){
    int a;
    cin >> a;

    val.push_back(a);
    inv[a]=i;
  }
  for(int i=0;i<n+5;i++){
    l[i]=i-1;
    r[i]=i+1;
  }

  val.push_back(1e9);

  vector<int> res;
  for(int i=1;i<=n;i++){
    int pt=inv[i];
    if(val[pt]!=i){continue;}
    if(r[pt]>n){continue;}

    int el,er;
    el=pt;
    er=r[pt];
    res.push_back(val[el]);
    res.push_back(val[er]);

    val[el]=1e9;
    val[er]=1e9;

    int ell=l[el];
    int err=r[er];
    r[ell]=err;
    l[err]=ell;
  }

  for(int i=0;i<n;i++){
    if(i){cout << " ";}
    cout << res[i];
  }cout << "\n";
  return 0;
}