#include <bits/stdc++.h>
using namespace std;
int strengths[800][800];
int pairs[800];
int used[800];
int best[800];
int best_idx[800];
int main() {
  int n;
  cin >> n;
  n *= 2;
  for (int ii = 1; ii < n; ii++) {
    for (int jj = 0; jj < ii; jj++) {
      int s;
      cin >> s;
      strengths[ii][jj] = strengths[jj][ii] = s;
    }
  }
  for (int blah = 0; blah < n / 2; blah++) {
    for (int ii = 0; ii < n; ii++) {
      best[ii] = best_idx[ii] = -1;
      if (used[ii]) continue;
      for (int jj = 0; jj < n; jj++) {
        if (jj == ii || used[jj]) continue;
        if (strengths[ii][jj] > best[ii]) {
          best[ii] = strengths[ii][jj];
          best_idx[ii] = jj;
        }
      }
    }
    for (int ii = 0; ii < n; ii++) {
      if (used[ii]) continue;
      if (ii == best_idx[best_idx[ii]]) {
        used[ii] = used[best_idx[ii]] = 1;
        pairs[ii] = best_idx[ii] + 1;
        pairs[best_idx[ii]] = ii + 1;
        break;
      }
    }
  }
  for (int ii = 0; ii < n; ii++) {
    cout << pairs[ii] << " ";
  }
  cout << endl;
}
