#include <bits/stdc++.h>

#define pb push_back
#define fi first
#define se second
#define all(v) v.begin(), v.end()

using namespace std;
using ll = uint64_t;

void solve() {
  const ll MOD = 1000000000 + 7;
  const ll BUBEN = MOD * MOD * 17;
  int n;
  cin >> n;
  vector<pair<ll,ll>> snakes(n);
  for (int i = 0; i < n; i++) {
    cin >> snakes[i].first >> snakes[i].second;
  }
  sort(all(snakes));
  ll res = 0;
  for (int i = 0; i < n; i++) {
    for (int j = i + 1; j < n; j++) {
      if (snakes[j].second > snakes[i].second) break;
      if (snakes[j].second == snakes[i].second) {
        ll dx = snakes[j].first - snakes[i].first;
        res += dx * dx;
        if (res >= BUBEN)
          res -= BUBEN;
      }
    }
  }
  res %= MOD;
  cout << res << endl;
}

int main() {
  int tests;
  cin >> tests;
  for (int t = 1; t <= tests; t++) {
    cout << "Case #" << t << ": ";
    solve();
  }
  return 0;
}