#include <bits/stdc++.h>   using namespace std;   long long a[222222], b[222222], c[222222], d[222222];   set<long long> st;   set<long long>::iterator it;   map<long long, long long> sp2;   int main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     long long n, m, k, x, s, i;     cin >> n >> m >> k;     cin >> x >> s;     for (i = 1; i <= m; i++) {       cin >> a[i];     }     for (i = 1; i <= m; i++) {       cin >> b[i];     }     for (i = 1; i <= k; i++) {       cin >> c[i];     }     for (i = 1; i <= k; i++) {       cin >> d[i];       st.insert(d[i]);       sp2[d[i]] = c[i];     }     long long ans = n * x;     long long rem;     long long temp;     for (i = 1; i <= m; i++) {       if (b[i] <= s) {         temp = 0;         rem = s - b[i];         it = st.upper_bound(rem);         if (it != st.begin()) {           it--;           temp += sp2[*it];         }         if (temp >= n)           ans = 0;         else           ans = min(ans, (n - temp) * a[i]);       }     }     temp = 0;     it = st.upper_bound(s);     if (it != st.begin()) {       it--;       temp += sp2[*it];     }     if (temp >= n)       ans = 0;     else       ans = min(ans, (n - temp) * x);     cout << ans << endl;     return 0;   }   