#include <iostream>

using namespace std;

bool check(long long d, long long a, long long k, long long b, long long m, long long x) {
    return (d - d / k) * a + (d - d / m) * b < x;
}

int main() {
    long long a, k, b, m, x;
    cin >> a >> k >> b >> m >> x;
    long long left = 0;
    long long right = 2 * x / (a + b) + 1;
    while (right - left > 1) {
        long long mid = (left + right) / 2;
        if (check(mid, a, k, b, m, x)) {
            left = mid;
        } else right = mid;
    }
    cout << right;
    return 0;
}