845C - Two TVs - CodeForces Solution

// © Urvish Patel

#include<bits/stdc++.h>
using namespace std;

#define fast  ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);

#define ll long long int

#define endll "\n"

#define f(var,srt,ed) for(int var=srt;var<ed;var++)
#define rf(var,srt,ed) for(int var=srt;var>ed;var--)
#define fe(var,cont) for(auto &var:cont)

#define pb push_back
#define begin begin()
#define end end()

#define gcd(a,b) __gcd(a,b)
#define lcm(a,b) ((a*b)/(__gcd(a,b)))

#define YES(x) cout<<"YES"<<x
#define NO(x) cout<<"NO"<<x


void solve()
{
    int n;
    cin>>n;

    vector<pair<int,int>> tv;

    f(i,0,n)
    {
        int l,r;
        cin>>l>>r;

        tv.pb({l,r});
    }

    sort(tv.begin,tv.end);

    int ed1=-1,ed2=-1;

    fe(it,tv)
    {
        int st=it.first,ed=it.second;

        bool check=false;

        if(ed1<st)
        {
            ed1=ed;
            check=true;
        }
        else if(ed2<st)
        {
            ed2=ed;
            check=true;
        }

        if(!check)
        {
            cout<<"NO"<<endl;
            return ;
        }
    }

    cout<<"YES"<<endl;

}


int main()
{
    fast

    int t=1;
    //cin>>t;

    f(_,0,t)
    {
        //cout<<"Case #"<<_<<": ";
        solve();
    }




    return 0;
}