#include <bits/stdc++.h>
using namespace std;
vector<pair<long long, string> > v[10020];
int main() {
  long long n, m;
  pair<long long, string> p;
  long long temp;
  cin >> n >> m;
  for (int i = 0; i < n; i++) {
    cin >> p.second;
    cin >> temp;
    cin >> p.first;
    v[temp].push_back(p);
  }
  for (int i = 1; i <= m; i++) {
    sort(v[i].begin(), v[i].end());
  }
  for (int i = 1; i <= m; i++) {
    int k = v[i].size();
    if (k < 2 || (k > 2 && v[i][k - 2].first == v[i][k - 3].first)) {
      cout << "?" << endl;
    } else {
      cout << v[i][k - 1].second << " " << v[i][k - 2].second << endl;
    }
  }
  return 0;
}
