tmp

#include <iostream>
#include <map>
#include <vector>
using namespace std;
using custom_map_t = map<size_t, vector<size_t>>;

vector<size_t> usedPoints(0);

static bool isInside(custom_map_t& map, const size_t& key) {
  return map.find(key) != map.end();
}

static bool isUsed(const size_t& key) {
  for (auto& jt : usedPoints) {
    if (jt == key) {
      return true;
    }
  }
  return false;
}

static bool isFound(custom_map_t& map,
                    const size_t& lookingIn,
                    const size_t& lookingFor) {
  usedPoints.push_back(lookingIn);
  for (auto& it : map[lookingIn]) {
    if (it == lookingFor) {
      usedPoints.clear();
      return true;
    }
    if (!isUsed(it)) {
      return isFound(map, it, lookingFor);
    }
  }
  usedPoints.clear();
  return false;
}
int main() {
  size_t pairAmount;
  custom_map_t pointMap;

  cout << "Enter the amount of pairs you want to enter later: ";
  cin >> pairAmount;

  cout << endl << "Enter pairs: " << endl;
  for (size_t i = 0, first, second; i < pairAmount; i++) {
    cout << i + 1 << ") ";
    cin >> first >> second;
    if (isInside(pointMap, first) || isInside(pointMap, second)) {
      if (isFound(pointMap, first, second)) {
        cout << "Already in" << endl;
      } else {
        cout << "Not found" << endl;
        pointMap[first].push_back(second);
        pointMap[second].push_back(first);
      }
    } else {
      cout << "First time see" << endl;
      pointMap[first].push_back(second);
      pointMap[second].push_back(first);
    }
  }
  return 0;
}