#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

const ll INF = 1e18;
void solve() {
  ll n, q;
  cin >> n >> q;
  map<ll, set<ll>> mp;
  rep(i, n) {
    ll a;
    cin >> a;
    if (mp.count(a) == 0)
      mp[a].insert(-1);
    mp[a].insert(i);
  }
  for (auto &[k, v] : mp)
    v.insert(n);
  vector<ll> dp(n, INF);
  dp[0] = 0;
  rep(qi, q) {
    ll b;
    cin >> b;
    vector<ll> nex(n, INF);
    rep(ci, n) {
      auto iter = mp[b].lower_bound(ci);
      auto upd = [&]() {
        nex[*iter] = min(nex[*iter], dp[ci] + abs(*iter - ci));
      };
      if (ci == *iter) {
        upd();
        continue;
      }
      if (*iter < n)
        upd();
      iter--;
      if (0 <= *iter)
        upd();
    }
    dp = nex;
  }
  ll ans = INF;
  rep(i, n) ans = min(ans, dp[i]);
  cout << ans << '\n';
}

int main() {
  std::cin.tie(nullptr);
  std::ios_base::sync_with_stdio(false);
  int T = 1;
  for (int t = 0; t < T; t++) {
    solve();
  }
  return 0;
}