#include "wiring.h"
#include<bits/stdc++.h>
#define int long long
#define pb push_back
#define mp make_pair
#define vb vector<bool>
#define vi vector<int>
#define vvi vector<vi>
#define pii pair<int,int>
#define vpii vector<pii>
#define f0r(i,n) for(int i = 0; i<n; i++)
#define FOR(i, k, n) for(int i = k; i<n; i++)
#define vout(v) for(auto u : v)cout<<u<<' '; cout<<endl;
const int mxn = 1e5 + 5;
using namespace std;
vi par(mxn), sz(mxn);
int find(int x){
if(x == par[x])return x;
return par[x] = find(par[x]);
}
void unite(int a, int b){
a = find(a); b = find(b);
if(a == b)return;
if(sz[a] < sz[b])swap(a,b);
sz[a] += sz[b];
par[b] = a;
}
long long min_total_length(std::vector<signed> r, std::vector<signed> b) {
int n = r.size(); int m = b.size();
vi v(n); vi w(m);
f0r(i,n)v[i] = r[i];
f0r(i, m)w[i] = b[i];
/*
vector<pair<int, pii>>edges;
f0r(i, n){
f0r(j, m){
edges.pb(mp(abs(v[i] - w[j]), mp(i, j + n)));
}
}
sort(edges.begin(), edges.end());
f0r(i, n + m){
par[i] = i; sz[i] = 1;
}
int ans = 0;
f0r(i, edges.size()){
int x = edges[i].second.first; int y = edges[i].second.second;
if(sz[find(x)] == 1 && sz[find(y)] == 1){
cout<<x<<' '<<y<<' '<<edges[i].first<<'\n';
unite(x,y);
ans += edges[i].first;
}
}
f0r(i, edges.size()){
int x = edges[i].second.first; int y = edges[i].second.second;
if(sz[find(x)] == 1 || sz[find(y)] == 1){
cout<<x<<' '<<y<<' '<<edges[i].first<<'\n';
unite(x,y);
ans += edges[i].first;
}
}
*/
vi lv(n);
vi rv(n);
vi lw(m);
vi rw(m);
int p1 = 0; int p2 = 0;
while(p1 < n || p2 < m){
if(p1 == n){
lw[p2] = p1-1;
p2++;
}
else if(p2 == m){
lv[p1] = p2-1;
p1++;
}
else{
if(v[p1] < w[p2]){
lv[p1] = p2-1;
p1++;
}
else{
lw[p2] = p1-1;
p2++;
}
}
}
p1 = n-1; p2 = m-1;
while(p1 >= 0 || p2 >= 0){
if(p1 == -1){
rw[p2] = p1+1;
p2--;
}
else if(p2 == -1){
rv[p1] = p2+1;
p1--;
}
else{
if(v[p1] > w[p2]){
rv[p1] = p2+1;
p1--;
}
else{
rw[p2] = p1+1;
p2--;
}
}
}
int cnt = 0;
set<int>s, t;
f0r(i, n)s.insert(v[i]);
f0r(i, m)t.insert(w[i]);
int ans = 0;
f0r(i, n){
if(rv[i] == m)rv[i] = -1;
}
f0r(i, m){
if(rw[i] == n)rw[i] = -1;
}
// vout(lw);
// vout(rw);
while(cnt < n + m){
if(s.size() == 0){
f0r(i, m){
if(t.count(w[i])){
int ret = 4e18;
if(lw[i] != -1)ret = min(ret, w[i] - v[lw[i]]);
if(rw[i] != -1)ret = min(ret, v[rw[i]] - w[i]);
ans += ret;
}
}
cnt = n + m;
}
else if(t.size() == 0){
f0r(i, n){
if(s.count(v[i])){
int ret = 4e18;
if(lv[i] != -1)ret = min(ret, v[i] - w[lv[i]]);
if(rv[i] != -1)ret = min(ret, w[rv[i]] - v[i]);
ans += ret;
}
}
cnt = n + m;
}
else{
for(auto A : s){
auto it = upper_bound(t.begin(), t.end(), A);
int nr = -4e18;
if(it != t.end())nr = *it;
int nl = -4e18;
if(it != t.begin()){
it--; nl = *it;
}
int x;
if(abs(nl - A) < abs(nr - A)){
x = nl;
}
else x = nr;
int dis = min(abs(nl - A), abs(nr - A));
it = upper_bound(s.begin(), s.end(), x);
int mr = -4e18;
if(it != s.end())mr = *it;
int ml = -4e18;
if(it != s.begin()){
it--; ml = *it;
}
int y;
if(abs(ml - x) < abs(mr - x)){
y = ml;
}
else y = mr;
if(y == A){
ans += abs(A - x);
// cout<<A<<' '<<x<<endl;
s.erase(A);
t.erase(x);
// cout<<s.size()<<' '<<t.size()<<"SDFSD"<<endl;
cnt += 2;
break;
}
// cout<<x<<' '<<y<<endl;
}
}
}
return ans;
/*
int ans = 0;
int mult = 1;
f0r(i, n-1){
ans += mult * (v[i+1] - v[i]);
mult++;
}
ans += max(n, m) * (w[0] - v.back());
mult = 1;
for(int i = m-1; i>0; i--){
ans += mult * (w[i] - w[i-1]);
mult++;
}
return ans;
*/
return 0;
}
