#include <bits/stdc++.h>
using namespace std;
typedef long long int lli;
int visited[500005];
bool iscyclic(vector<vector<int> > &ed,int st,int par)
{
visited[st]=1;
for(int i=0;i<ed[st].size();i++)
{
if(!visited[ed[st][i]])
{
if(iscyclic(ed,ed[st][i],st))
return true;
}
else if(ed[st][i]!=par)
return true;
}
return false;
}
class pnt
{
public:
int no,y;
};
int main() {
int n,x,y;
cin>>n;
pnt pt[2*n];
for(int i=0;i<n;i++)
{
cin>>x>>y;
x--;
y--;
pt[x].no=pt[y].no=i;
pt[x].y=y;
pt[y].y=y;
}
set<pair<int,int> > curr;
vector<vector<int> > mp(n);
int fl=1;
int ed=-1;
for(int i=0;i<2*n and ed<n;i++)
{
//ed+=n;
if(pt[i].y!=i)
{
if(!curr.empty())
{
auto itr=curr.lower_bound({pt[i].y,-1});
if(itr!=curr.begin())
itr--;
if(itr!=curr.end() and itr->first<pt[i].y)
{
// cout<<i<<" "<<itr->first<<"\n";
while(itr!=curr.begin() and ed<n)
{
int e=itr->second;
mp[pt[i].no].push_back(e);
mp[e].push_back(pt[i].no);
ed++;
itr--;
}
if(itr==curr.begin())
{
int e=itr->second;
mp[pt[i].no].push_back(e);
mp[e].push_back(pt[i].no);
ed++;
}
}
}
curr.insert({pt[i].y,pt[i].no});
}
else
{
curr.erase(curr.find({pt[i].y,pt[i].no}));
}
}
if(iscyclic(mp,0,0))
fl=0;
for(int i=0;i<n;i++)
{
if(!visited[i])
{
//cout<<i<<" "<<"\n";
fl=0;
break;
}
}
if(fl==0)
{
cout<<"NO\n";
}
else
cout<<"YES\n";
return 0;
}
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