#include "wiring.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
const ll MOD = 998244353;
const ll INF = 1e18+5;
const ld EPS = 1e-12;
#define endl "\n"
#define sp <<" "<<
#define REP(i, a, b) for(ll i = a; i < b; i++)
#define dbg(x) cout << #x << " = " << x << endl
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define fast_io() ios_base::sync_with_stdio(false); cin.tie(NULL)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) ((ll)(x).size())
struct custom_hash {
static uint64_t splitmix64(uint64_t x) {
// http://xorshift.di.unimi.it/splitmix64.c
x += 0x9e3779b97f4a7c15;
x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
return x ^ (x >> 31);
}
size_t operator()(uint64_t x) const {
static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
return splitmix64(x + FIXED_RANDOM);
}
};
template <typename Key, typename Value>
using hash_map = unordered_map<Key, Value, custom_hash>;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
// uniform_int_distribution<int>(a, b)(rng);
// shuffle(all(a), rng);
const int MAXN = 1e5;
long long min_total_length(vector<int> r, vector<int> s) {
int n = r.size(), m = s.size(), t = n + m;
auto cost = [&](ll i, ll j) -> ll {
i--, j--;
return abs(r[i] - s[j]);
};
vector<vector<ll>> dp(n+1, vector<ll>(m+1, INF));
dp[0][0] = 0;
function<ll(ll, ll)> perf = [&](ll i, ll j) -> ll {
if (dp[i][j] != INF)
return dp[i][j];
if (i == 0 or j == 0)
return INF;
ll c = cost(i, j);
if (i > 0) dp[i][j] = min(dp[i][j], perf(i-1, j) + c);
if (j > 0) dp[i][j] = min(dp[i][j], perf(i, j-1) + c);
if (i > 0 and j > 0) dp[i][j] = min(dp[i][j], perf(i-1, j-1) + c);
return dp[i][j];
};
REP(i, 1, n+1) {
REP(j, 1, m+1) {
perf(i, j);
}
}
REP(i, 0, n+1) {
REP(j, 0, m+1) {
// cerr << i sp j sp dp[i][j] << endl;
}
}
return dp[n][m];
}
signed main() {
int n, m; cin >> n >> m;
vector<int> a(n), b(m);
REP(i, 0, n)
cin >> a[i];
REP(i, 0, m)
cin >> b[i];
cout << min_total_length(a, b);
}
