#include<iostream>
#include<algorithm>
#include<vector>
#include "walk.h"
using namespace std;
int N;
long long min_distance(std::vector<int> x, std::vector<int> h, std::vector<int> l, std::vector<int> r, std::vector<int> y, int s, int g)
{
N=x.size();
vector<pair<int,int>>inters;
for(int i=0;i<l.size();i++)
{
inters.push_back({l[i],r[i]});
}
sort(inters.begin(),inters.end());
if(inters[0].first!=0)return -1;
for(int i=1;i<l.size();i++)
{
if(inters[i].first==inters[i-1].second)continue;
return -1;
}
if(inters.back().second!=N-1)return -1;
long long ans=1LL*x[N-1]-1LL*x[0]+2LL*h[0];
return ans;
}
