#include <bits/stdc++.h>
using namespace std;
int main() {
  long long n, m, x, y, k;
  cin >> n >> m;
  long long a[n], b[m];
  cin >> x >> k >> y;
  for (long long i = 0; i < n; i++) cin >> a[i];
  for (long long i = 0; i < m; i++) cin >> b[i];
  vector<long long> adj[n];
  long long z[n];
  long long ind = 0;
  for (long long i = 0; i < n; i++) {
    if (ind >= m) {
      adj[ind].push_back(a[i]);
      continue;
    }
    if (b[ind] == a[i]) {
      if (ind - 1 >= 0)
        z[ind] = max(b[ind], b[ind - 1]);
      else
        z[ind] = b[ind];
      ind++;
    } else
      adj[ind].push_back(a[i]);
  }
  if (ind < m - 1) {
    cout << "-1\n";
    return 0;
  }
  z[ind] = b[m - 1];
  ind = 0;
  long long ans = 0;
  int f = 0;
  for (auto &it : adj) {
    long long itl = it.size();
    if (itl == 0) {
      ind++;
      continue;
    }
    long long mxv = -1;
    for (auto &it2 : it) mxv = max(mxv, it2);
    if (itl < k) {
      if (mxv < z[ind])
        ans += itl * y;
      else {
        f = 1;
        break;
      }
    } else {
      if (x >= y * k) {
        if (mxv < z[ind])
          ans += itl * y;
        else {
          ans = ans + (itl - k) * y + x;
        }
      } else {
        ans += (itl / k) * x + (itl % k) * y;
      }
    }
    ind++;
  }
  if (f == 1)
    cout << "-1\n";
  else
    cout << ans << "\n";
  return 0;
}
