#include <bits/stdc++.h>
#include "railroad.h"
using namespace std;
vector<vector<int>> g;
vector<bool> volt;
int bejar(int akt){
volt[akt] = true;
int ret = 1;
for(int x : g[akt])
if(!volt[x])
ret += bejar(x);
return ret;
}
long long plan_roller_coaster(std::vector<int> s, std::vector<int> t) {
int n = (int) s.size();
vector<int> compr;
compr.reserve(2*n);
for(int x : s)
compr.push_back(x);
for(int x : t)
compr.push_back(x);
sort(compr.begin(), compr.end());
compr.erase(unique(compr.begin(), compr.end()), compr.end());
vector<int> va(n), vb(n);
for(int i = 0; i < n; i++){
va[i] = lower_bound(compr.begin(), compr.end(), s[i])-compr.begin();
vb[i] = lower_bound(compr.begin(), compr.end(), t[i])-compr.begin();
}
int m = (int)compr.size();
vector<int> fok(m, 0);
g.resize(m);
for(int i = 0; i < n; i++){
fok[va[i]]++;
fok[vb[i]]--;
g[va[i]].push_back(vb[i]);
}
fok[0]--;
fok[m-1]++;
for(int i = 0; i < m-1; i++){
if(fok[i] < 0)
g[i].push_back(i+1);
if(fok[i] <= 0)
fok[i+1] += fok[i];
else
return 1;
}
volt.assign(m, false);
if(fok[m-1] == 0 && bejar(0) == m)
return 0;
return 1;
}
