#include<bits/stdc++.h> #define nl 1000005 using namespace std; int n; int x[nl], y[nl]; namespace Subtask2 { void Solve() { string res = ""; for( int mask = 1; mask < ( 1<<n ); mask ++ ) { bool test = true; vector<bool> used( n+1, false ); vector<int> cntX( n+1, 0 ), cntY( n+1, 0 ); for( int i = 0; i < n; i ++ ) if(( mask >> i ) & 1) { used[i+1] = true; cntX[x[i+1]] ++ ; if( cntX[x[i+1]] > 2 ) { test = false; break; } cntY[y[i+1]] ++ ; if( cntY[y[i+1]] > 2 ) { test = false; break; } } if( test ) { for( int i = 1; i <= n; i ++ ) { if( used[i] ) continue; bool okX1 = false; bool okX2 = false; bool okX = false; for( int j = 1; j <= n; j ++ ) if( j != i ) { if( !used[j] ) continue; if( x[i] == x[j] ) { if( y[j] < y[i] ) okX1 = true; if( y[j] > y[i] ) okX2 = true; } okX = okX1 & okX2; if( okX ) break; } bool okY1 = false; bool okY2 = false; bool okY = false; for( int j = 1; j <= n; j ++ ) if( j != i ) { if( !used[j] ) continue; if( y[i] == y[j] ) { if( x[j] < x[i] ) okY1 = true; if( x[j] > x[i] ) okY2 = true; } okY = okY1 & okY2; if( okY ) break; } if( !okX && !okY ) { test = false; break; } } } if( test ) { for( int i = 1; i <= n; i ++ ) if( used[i] ) res += "1"; else res += "0"; break; } } cout << res << "\n"; } } int main() { ios_base :: sync_with_stdio( false ); cin.tie( NULL ); cout.tie( NULL ); #define File "SLAMP" if( fopen( File ".inp", "r" ) ) { freopen( File ".inp", "r", stdin ); freopen( File ".out", "w", stdout ); } cin >> n; for( int i = 1; i <= n; i ++ ) cin >> x[i] >> y[i]; if( n <= 16 ) Subtask2 :: Solve(); return 0; }

Main.cpp: In function 'int main()':
Main.cpp:108:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  108 |         freopen( File ".inp", "r", stdin );
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:109:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  109 |         freopen( File ".out", "w", stdout );
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~