#include "wiring.h"
#include<bits/stdc++.h>
using namespace std;
const int N = 1010;
long long dp[N][N];
int a[N], b[N];
long long min_total_length(std::vector<int> R, std::vector<int> B) {
int n = R.size(), m = B.size();
for(int i = 1; i <= n; i++) a[i] = R[i - 1];
for(int i = 1; i <= m; i++) b[i] = B[i - 1];
memset(dp, 61, sizeof(dp));
dp[0][0] = 0;
for(int i = 1; i <= n; i++) for(int j = 1; j <= m; j++) {
dp[i][j] = min({dp[i - 1][j - 1], dp[i][j - 1], dp[i - 1][j]}) + abs(a[i] - b[j]);
}
return dp[n][m];
}
#ifdef ngu
int main() {
freopen ("task.inp", "r", stdin);
freopen ("task.out", "w", stdout);
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);
return 0;
}
#endif // ngu
