#include <bits/stdc++.h> #define fi first #define sc second #define int long long #define pii pair<int,int> using namespace std; const int N=1e6+5; const int N2=2e5+5; const int N5=5e5+5; const int N1=1e6+5; const int inf=1e18+7; const int MOD=1e9+7; int n; pii a[N],b[N]; bool kq=false; void dequy(vector<int> &vc,int n) { if(vc.size()==n) { if(kq==true) return; vector<bool> ktra(n+2,false); int demx[3*n]={0}, demy[3*n]={0}; vector<int> tdx[3*n]; vector<int> tdy[3*n]; for(int i=0;i<vc.size();i++) { int x=a[i].fi; int y=a[i].sc; if(vc[i]==1) { ktra[i]=true; demx[x]++; demy[y]++; tdx[x].push_back(y); tdy[y].push_back(x); if(demx[x]>2 ||demy[y]>2) return; } } bool check=true; for(int i=0;i<n;i++) { int x=a[i].fi; int y=a[i].sc; if(ktra[i]==true) continue; if(tdx[x].size()<=1 && tdy[y].size()<=1) {check=false; break;} int xfi=-1; int xsc=-1; int yfi=-1; int ysc=-1; if(tdx[x].size()==2) xfi=tdx[x][0], xsc=tdx[x][1]; if(tdy[y].size()==2) yfi=tdy[y][0], ysc=tdy[y][1]; if(min(xfi,xsc)<y && y<max(xfi,xsc)) continue; if(min(yfi,ysc)<x && x<max(yfi,ysc)) continue; check=false; break; } if(check==true) { for(int i:vc) cout<<i; kq=true; } return; } vc.push_back(0); dequy(vc,n); vc.pop_back(); vc.push_back(1); dequy(vc,n); vc.pop_back(); } void dq(int n) { vector<int> vc; dequy(vc,n); } vector<int> nen; int val[N]; int sdy[N]; int res[N]; vector<pii> sy[N]; int maxy=INT_MIN; int32_t main() { //freopen("SLAMP.inp","r",stdin); //freopen("SLAMP.out","w",stdout); ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin>>n; for(int i=0;i<n;i++) { cin>>a[i].fi>>a[i].sc; nen.push_back(a[i].fi); nen.push_back(a[i].sc); } sort(nen.begin(),nen.end()); nen.erase(unique(nen.begin(),nen.end()),nen.end()); for(int i=0;i<nen.size();i++) val[nen[i]]=i+1; for(int i=0;i<n;i++) { a[i].fi=val[a[i].fi]; a[i].sc=val[a[i].sc]; maxy=max(maxy,a[i].sc); sdy[a[i].sc]++; } if(n<=16) { dq(n); } else{ for(int i=0;i<n;i++) { int x=a[i].fi; int y=a[i].sc; if(sdy[y]<=2) res[i]=1; else sy[y].push_back({x,i}); } for(int i=1;i<=maxy;i++) { if(sy[i].empty()==true) continue; sort(sy[i].begin(),sy[i].end()); int st=sy[i][0].sc; int ed=sy[i][sy[i].size()-1].sc; res[st]=1; res[ed]=1; } for(int i=0;i<n;i++) cout<<res[i]; } }