#include <bits/stdc++.h> #define task "SLAMP" #define int long long #define pii pair <int, int> #define fi first #define se second #define szf sizeof #define sz(s) (int)((s).size()) #define all(v) (v).begin(), (v).end() using namespace std; typedef long long ll; typedef long double ld; template <class T> void minimize (T &t, T f) {if (t > f) t = f;} template <class T> void maximize (T &t, T f) {if (t < f) t = f;} const int maxN = 2e5 + 5; const ld Eps = 1e-12; const int inf = 1e18 + 7; const int Log = 20; const int mod = 1e9 + 7; // mt19937_64 rd (chrono :: steady_clock :: now ().time_since_epoch ().count ()); // int Rand (int l, int r) {return uniform_int_distribution <int> (l, r) (rd);} int n; pii a[maxN]; vector <int> posX[maxN], posY[maxN]; vector <int> px, py; namespace sub2 { int act[maxN]; bool check () { for (auto it : px) { int cnt = 0; for (auto i : posX[it]) { cnt += act[i]; } if (cnt > 2) { return false; } } for (auto it : py) { int cnt = 0; for (auto i : posY[it]) { cnt += act[i]; } if (cnt > 2) { return false; } } for (int i = 1; i <= n; i ++) { if (act[i] == 1) { continue; } auto [x, y] = a[i]; int ok = 0; { int cntL = 0; int cntR = 0; for (auto it : posX[x]) { if (act[it] == 0) { continue; } int yl = a[it].se; // if (i == 4) { // cout << yl << ' ' << y << '\n'; // } if (yl < y) { cntL ++; } else if (yl > y) { cntR ++; } } // if (i == 4) { // cout << cntL << ' ' << cntR << '\n'; // } if (cntL != 0 && cntR != 0) { ok = 1; } } if (ok) { continue; } { int cntL = 0; int cntR = 0; for (auto it : posY[y]) { if (act[it] == 0) { continue; } int xl = a[it].fi; // if (i == 4) { // cout << xl << ' ' << it << '\n'; // } if (xl < x) { cntL ++; } else if (xl > x) { cntR ++; } } // if (i == 4) { // cout << cntL << ' ' << cntR << '\n'; // } if (cntL != 0 && cntR != 0) { ok = 1; } } //cout << i << ' ' << ok << '\n'; if (ok == 0) { return false; } } return true; } void sol () { // for (int i = 1; i <= n; i ++) { // char c; // cin >> c; // act[i] = (c - '0'); // //cout << act[i] << ' '; // } // cout << check (); // return; for (int mask = 0; mask < (1 << n); mask ++) { for (int i = 1; i <= n; i ++) { act[i] = ((mask >> (i - 1)) & 1); } if (check ()) { for (int i = 1; i <= n; i ++) { cout << act[i]; } } } } } inline void Solve () { cin >> n; for (int i = 1; i <= n; i ++) { cin >> a[i].fi >> a[i].se; } for (int i = 1; i <= n; i ++) { posX[a[i].fi].push_back (i); posY[a[i].se].push_back (i); px.push_back (a[i].fi); py.push_back (a[i].se); } sort (all (px)); px.erase (unique (all (px)), px.end ()); sort (all (py)); py.erase (unique (all (py)), py.end ()); sub2 :: sol (); return; } signed main () { cin.tie (nullptr) -> sync_with_stdio (false); if (fopen (task".inp", "r")) { freopen (task".inp", "r", stdin); freopen (task".out", "w", stdout); } int t = 1; //cin >> t; while (t --) { Solve (); } return 0; } // Stress test : // Check constant : // Check taskname : // Check debug : // Check subtask :

Main.cpp: In function 'int main()':
Main.cpp:169:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  169 |         freopen (task".inp", "r", stdin);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:170:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  170 |         freopen (task".out", "w", stdout);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~