#include <bits/stdc++.h>
using namespace std;
template <class T>
void print(T& x) {
  cout << x;
}
template <class T, class U>
void print(pair<T, U>& p) {
  cout << "(";
  print(p.first);
  cout << ", ";
  print(p.second);
  cout << ")";
}
template <class T>
void print(vector<T>& v) {
  cout << "{";
  if (((int)(v).size())) print(v[0]);
  for (int i = 1; i < ((int)(v).size()); i++) cout << ", ", print(v[i]);
  cout << "}\n";
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  int N, M, K;
  long long X, Y;
  cin >> N >> M;
  cin >> X >> K >> Y;
  vector<int> A(N + 1);
  for (int i = 0; i < N; i++) {
    cin >> A[i];
  }
  A[N] = 0;
  vector<int> B(M + 2);
  for (int i = 1; i <= M; i++) {
    cin >> B[i];
  }
  B[M + 1] = 0;
  int ai = 0;
  long long C = 0;
  for (int i = 1; i <= M + 1; i++) {
    int st = ai;
    int m = -1;
    while (ai <= N && A[ai] != B[i]) {
      m = max(m, A[ai]);
      ai++;
    }
    if (ai == N + 1) {
      cout << -1 << endl;
      return 0;
    }
    long long cnt = ai - st;
    if (m > B[i - 1] && m > B[i]) {
      if (cnt < K) {
        cout << -1 << endl;
        return 0;
      }
      C += X;
      cnt -= K;
    }
    if (Y * K <= X) {
      C += Y * cnt;
    } else {
      C += cnt / K * X + cnt % K * Y;
    }
    ai++;
  }
  cout << C << "\n";
}
