#include "railroad.h"
#include<bits/stdc++.h>
using namespace std;
typedef set<pair<int,int> >::iterator sit;
/*operator < (pair<int,int> a, pair<int,int> b){
if(a.first<b.first)return true;
if(b.first>a.first)return false;
return a.second<b.second;
}*/
long long plan_roller_coaster(std::vector<int> s, std::vector<int> t) {
int n = (int) s.size();
set<pair<int,int> > S;
for(int i=0;i<n;i++){//cout<<s[i]<<" "<<t[i]<<endl;
S.insert(pair<int,int> (s[i],t[i]));
}
int pos=-10000;
while(!S.empty()){
//cout<<pos<<endl;
sit it=S.upper_bound(pair<int,int>(pos-1,1000000001));
if(it==S.end()){
return 1;
}
pos=it->second;
S.erase(it);
}
return 0;
}
