#include <bits/stdc++.h>
using namespace std;
int const oo = 1e9, bound = 1e6, mod = oo + 7;
long long const OO = 1e18;
int main() {
  int n;
  vector<pair<int, pair<int, int> > > tt;
  scanf("%d", &n);
  for (int i = 1; i < n * 2; i++) {
    for (int j = 0; j < i; j++) {
      int a;
      scanf("%d", &a);
      tt.push_back(make_pair(-a, make_pair((i), (j))));
    }
  }
  sort(tt.begin(), tt.end());
  int rel[1000], cop = n;
  memset(rel, -1, sizeof rel);
  for (int(i) = 0; (i) < (tt.size()); (i)++) {
    if (!n) break;
    if (rel[tt[i].second.first] != -1 || rel[tt[i].second.second] != -1)
      continue;
    rel[tt[i].second.first] = tt[i].second.second;
    rel[tt[i].second.second] = tt[i].second.first;
    n--;
  }
  for (int(i) = 0; (i) < (2 * cop); (i)++) {
    if (rel[i] == -1) {
      tt[tt.size() + 1].first = 11;
    }
    printf("%d ", rel[i] + 1);
  }
  puts("");
  return 0;
}
