/// In The Name Of God
#include <bits/stdc++.h>
#define f first
#define s second
#define pb push_back
#define pp pop_back
#define mp make_pair
#define sz(x) (int)x.size()
#define sqr(x) ((x) * 1ll * (x))
#define all(x) x.begin(), x.end()
#define rep(i, l, r) for (int i = (l); i <= (r); i++)
#define per(i, l, r) for (int i = (l); i >= (r); i--)
#define Kazakhstan ios_base :: sync_with_stdio(0), cin.tie(0), cout.tie(0);
#define nl '\n'
#define ioi exit(0);
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
const int N = (int)4e5 + 7;
const int inf = (int)1e9 + 7;
const int mod = (int)1e9 + 7;
const ll linf = (ll)1e18 + 7;
const int dx[] = {-1, 0, 1, 0, 1, -1, -1, 1};
const int dy[] = {0, 1, 0, -1, 1, -1, 1, -1};
using namespace std;
int sz;
pair <ll, int> t[N];
ll dp[N], s[N];
int nxt[N];
ll get(int l, int r) {
if (nxt[l] == -1) assert(0);
int n, m;
int id = nxt[l] - 1;
n = id - l + 1;
m = r - id;
ll res = 0;
res += t[id].f * (id - l + 1) - (s[id] - s[l - 1]);
res += (s[r] - s[id]) - t[id + 1].f * (r - id);
res += max(n, m) * (t[id + 1].f - t[id].f);
return res;
}
ll min_total_length(vector <int> _r, vector <int> _b) {
for (auto it : _r) t[++sz] = {it, 0};
for (auto it : _b) t[++sz] = {it, 1};
sort (t + 1, t + 1 + sz);
rep(i, 1, sz) s[i] = s[i - 1] + t[i].f;
{ /// calc next
int pos[2] = {-1, -1};
per(i, sz, 1) {
int b = t[i].s;
nxt[i] = pos[b ^ 1];
pos[b] = i;
}
}
memset(dp, 0x3f, sizeof(dp));
dp[0] = 0;
int cnt = 0, last = -1;
int pos[2] = {-1, -1};
int R = -1;
rep(i, 1, sz) {
if (t[i].s != last) {
cnt = 1, last = t[i].s;
R = nxt[i];
if (nxt[R] == -1) R = sz;
else R = nxt[R] - 1;
}
else ++cnt;
if (pos[t[i].s ^ 1] != -1) { /// go to the left
int j = pos[t[i].s ^ 1];
ll sum = s[i] - s[j];
dp[i] = min(dp[i], dp[i - 1] + t[i].f - t[j].f);
dp[i] = min(dp[i], dp[j - 1] + sum - (ll)t[j].f * (i - j));
}
{ /// go to the right
int id = -1;
int cur = 0;
if (nxt[i] == -1) continue;
while (R - nxt[i] + 1 > nxt[i] - i) R--;
//cerr << i << ' ' << nxt[i] << ' ' << R << nl;
rep(j, max(nxt[i], R - 100), R) {
dp[j] = min(dp[j], min(dp[i - 1], dp[i]) + get(i, j));
if (id == -1) id = j;
++cur;
//if (cur > id - i) break;
}
}
pos[t[i].s] = i;
}
return dp[sz];
}
#ifdef IOI2018
namespace read {
void read() {
int n, m;
assert(2 == scanf("%d %d", &n, &m));
vector<int> r(n), b(m);
for(int i = 0; i < n; i++)
assert(1 == scanf("%d", &r[i]));
for(int i = 0; i < m; i++)
assert(1 == scanf("%d", &b[i]));
long long res = min_total_length(r, b);
printf("%lld\n", res);
ioi
}
}
int main() {
#ifdef IOI2018
freopen ("in.txt", "r", stdin);
freopen ("slow.out", "w", stdout);
#endif
read :: read();
ioi
}
#endif
//// 000 111 111111111
