#include <bits/stdc++.h>
using namespace std;
int x, k, y;
long long passed(vector<int> &arr, int range) {
  vector<int> pos;
  int n = arr.size();
  for (int i = 0; i < n; i++) {
    if (arr[i] > range) {
      pos.push_back(i);
    }
  }
  if (pos.size() and k > n) return -1;
  if (k * y <= x) {
    if (pos.size() == 0)
      return (long long)y * (long long)n;
    else {
      return (long long)(n - k) * (long long)y + (long long)x;
    }
  }
  {
    long long bz = n / k;
    long long r = n - bz * k;
    return bz * (long long)x + r * y;
  }
}
int main() {
  int n, m;
  cin >> n >> m;
  cin >> x >> k >> y;
  vector<int> a(n), b(m);
  map<int, bool> bm;
  for (int &i : a) cin >> i;
  for (int &i : b) {
    cin >> i;
    bm[i] = 1;
  }
  vector<int> c;
  for (int i : a) {
    if (bm[i]) c.push_back(i);
  }
  if (c.size() != b.size()) {
    cout << -1 << endl;
    return 0;
  }
  for (int i = 0; i < b.size(); i++) {
    if (b[i] != c[i]) {
      cout << -1 << endl;
      return 0;
    }
  }
  a.push_back(INT_MIN);
  b.push_back(INT_MIN);
  bm[INT_MIN] = 1;
  int idx = 0;
  int last = INT_MIN;
  long long ans = 0;
  while (idx < n) {
    vector<int> tmp;
    for (; idx < n; idx++) {
      if (bm[a[idx]]) {
        break;
      } else
        tmp.push_back(a[idx]);
    }
    if (tmp.size() > 0) {
      long long ret = passed(tmp, max(last, a[idx]));
      if (ret == -1) {
        cout << -1 << endl;
        return 0;
      } else {
        ans += ret;
      }
    }
    last = a[idx++];
  }
  cout << ans << endl;
}
