#include <iostream>
#include <cassert>
#include <vector>
#include <map>
#include <cmath>

using namespace std;

int main() {
  int N, Q; cin >> N >> Q;
  vector<int> A(N);
  map<int, vector<int>> mp;
  vector<vector<int>> dp(Q + 1, vector<int>(N, 2e9));
  for (int i = 0; i < N; i++) {
    cin >> A[i];
    mp[A[i]].push_back(i);
  }

  dp[0][0] = 0;
  int prv = -1;
  for (int i = 0; i < Q; i++) {
    int b; cin >> b;
    if (i == 0) {
      for (int j: mp[b]) {
	dp[i + 1][j] = min(dp[i + 1][j], dp[i][0] + j);
      }
    } else {
      for (int j: mp[prv]) {
	for (int k: mp[b]) {
	  dp[i + 1][k] = min(dp[i + 1][k], dp[i][j] + (abs(j - k)));
	}
      }
    }
    prv = b;
  }

  int mi = 2e9;
  for (int i: mp[prv]) {
    mi = min(mi, dp[Q][i]);
  }
  cout << mi << endl;
  return 0;
}