#include <bits/stdc++.h>
using namespace std;
using ll = unsigned long long;
int N, M;
ll X, K, Y;
int main() {
  cin >> N >> M >> X >> K >> Y;
  vector<int> A(N);
  vector<int> B(M);
  map<int, int> A_ri;
  int max_idx_A = 0;
  for (int i = 0; i < N; i++) {
    cin >> A[i];
    A_ri[A[i]] = i;
    if (A[i] > A[max_idx_A]) {
      max_idx_A = i;
    }
  }
  for (int i = 0; i < M; i++) cin >> B[i];
  int last_idx = -1;
  set<int> A_idx_keep;
  vector<int> A_idx_keep_vec;
  for (int i = 0; i < M; i++) {
    if (A_ri.find(B[i]) == A_ri.end()) {
      cout << -1 << endl;
      return 0;
    } else {
      if (A_ri[B[i]] < last_idx) {
        cout << -1 << endl;
        return 0;
      } else {
        A_idx_keep.insert(A_ri[B[i]]);
        A_idx_keep_vec.push_back(A_ri[B[i]]);
        last_idx = A_ri[B[i]];
      }
    }
  }
  auto cost_to_destroy = [&](vector<int> segment, int left, int right) {
    if (segment.size() == 0) return (ll)0;
    ll seg_max = *max_element(segment.begin(), segment.end());
    if (segment.size() < K) {
      if (max(left, right) < seg_max) {
        cout << -1 << endl;
        exit(0);
      } else {
        return (ll)segment.size() * Y;
      }
    }
    if (Y * K < X) {
      if (max(left, right) > seg_max) {
        return (ll)segment.size() * Y;
      }
      return (ll)(segment.size() - K) * Y + X;
    }
    return (ll)(segment.size() % K) * Y + (segment.size() / K) * X;
  };
  ll ans = 0;
  A_idx_keep_vec.push_back(N);
  bool max_ok = false;
  for (int i = 0; i < A_idx_keep_vec.size(); i++) {
    int left = -1;
    int right = A_idx_keep_vec[i];
    vector<int> segment;
    if (i > 0) left = A_idx_keep_vec[i - 1];
    for (int j = left + 1; j < right; j++) {
      segment.emplace_back(A[j]);
    }
    int left_boundary = -1;
    if (left != -1) left_boundary = A[left];
    int right_boundary = -1;
    if (right != N) right_boundary = A[right];
    ans += cost_to_destroy(segment, left_boundary, right_boundary);
  }
  cout << ans << endl;
}
