#include <bits/stdc++.h>
#include "railroad.h"
using namespace std;
long long adj[20][20];
long long memo[20][66000];
long long tsp(int x,int bm){
if(memo[x][bm]!=-1)return memo[x][bm];
if(bm==0)return memo[x][bm]=0;
long long ans=1000000000000000010;
int bm2=bm;
while(bm2&(-bm2)){
int y=__builtin_ctz(bm2);
ans=min(ans,tsp(y,bm-(bm2&(-bm2)))+adj[x][y]);
bm2-=(bm2&(-bm2));
}
return memo[x][bm]=ans;
}
long long plan_roller_coaster(vector<int> s, vector<int> t) {
int n=(int)s.size();
if(n>16){
set<pair<int,int> > st;
for(int i=0;i<n;i++)st.insert(make_pair(s[i],t[i]));
int cur=1;
while(!st.empty()){
set<pair<int,int> >::iterator it=st.lower_bound(make_pair(cur,-1));
if(it==st.end())return 0;
cur=it->second;
--it;
}
return 1;
}
for(int i=0;i<n;i++){
for(int j=0;j<n;j++){
if(i==j)adj[i][j]=0;
else adj[i][j]=max(0,t[i]-s[j]);
}
}
for(int i=0;i<n;i++){
for(int j=0;j<n;j++){
for(int k=0;k<n;k++){
adj[j][k]=min(adj[j][k],adj[j][i]+adj[i][k]);
}
}
}
memset(memo,-1,sizeof(memo));
long long ans=1000000000000000010;
for(int i=0;i<n;i++){
ans=min(ans,tsp(i,(1<<n)-1-(1<<i)));
}
return ans;
}
