#include <bits/stdc++.h>
using namespace std;
const long long INF = 1e9 + 5, N = 5e4 + 5, mod = 1e9 + 7, M = 7e5 + 5;
int main() {
  long long n, m;
  cin >> n >> m;
  long long x, k, y;
  cin >> x >> k >> y;
  long long a[n + 5], b[m + 5];
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
  }
  for (int i = 1; i <= m; i++) {
    cin >> b[i];
  }
  if (m > n) {
    cout << -1 << endl;
    return 0;
  }
  long long idx = 1, mx = 0, col = 0, last = 0, ans = 0;
  for (int i = 1; i <= n; i++) {
    if (a[i] == b[idx]) {
      if (x < y * k) {
        if (col / k == 0) {
          if (mx > a[i] && mx > last) {
            cout << -1 << endl;
            return 0;
          }
          ans += (col * y);
        } else {
          long long pol = col / k, ost = (col % k);
          ans += (ost * y);
          ans += (pol * x);
        }
      }
      if (x == y * k) {
        if (col / k == 0) {
          if (mx > a[i] && mx > last) {
            cout << -1 << endl;
            return 0;
          }
          ans += (col * y);
        } else {
          long long pol = col / k, ost = (col % k);
          ans += (ost * y);
          ans += (pol * x);
        }
      }
      if (x > y * k) {
        if (col / k == 0) {
          if (mx > a[i] && mx > last) {
            cout << -1 << endl;
            return 0;
          }
          ans += (col * y);
        } else {
          if (mx > a[i] && mx > last) {
            long long ost = col - k;
            ans += x;
            ans += (ost * y);
          } else {
            ans += (col * y);
          }
        }
      }
      mx = 0;
      col = 0;
      last = a[i];
      idx++;
      continue;
    }
    mx = max(mx, a[i]);
    col++;
  }
  if (x < y * k) {
    if (col / k == 0) {
      if (mx > last) {
        cout << -1 << endl;
        return 0;
      }
      ans += (col * y);
    } else {
      long long pol = col / k, ost = (col % k);
      ans += (ost * y);
      ans += (pol * x);
    }
  }
  if (x == y * k) {
    if (col / k == 0) {
      if (mx > last) {
        cout << -1 << endl;
        return 0;
      }
      ans += (col * y);
    } else {
      long long pol = col / k, ost = (col % k);
      ans += (ost * y);
      ans += (pol * x);
    }
  }
  if (x > y * k) {
    if (col / k == 0) {
      if (mx > last) {
        cout << -1 << endl;
        return 0;
      }
      ans += (col * y);
    } else {
      if (mx > last) {
        long long ost = col - k;
        ans += x;
        ans += (ost * y);
      } else {
        ans += (col * y);
      }
    }
  }
  if (idx != m + 1) ans = -1;
  cout << ans << endl;
}
