#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <vector>
#include <string>
#include <cstring>

using namespace std;

const int MAXN = 5001;

int x, y, a, b, l, maxi;
int m[MAXN], m1[MAXN];

void step(int l) {
    for (int i = 0; i <= maxi; i++) m1[i] = -1;
    for (int it = 0; it <= maxi; it++) {
        if (m[it] != -1) {
            if (x > y) {
                for(int i = 0; i <= it; i++) {
                    int b = max(0, (l - x * i + y - 1) / y);
                    if (m[it] < b) continue;
                    m1[it - i] = max(m1[it - i], m[it] - b);
                    if (l <= i * x) break;
                }
            } else {
                for(int i = 0; i <= m[it]; i++) {
                    int b = max(0, (l - y * i + x - 1) / x);
                    if (it < b) continue;
                    m1[it - b] = max(m1[it - b], m[it] - i);
                    if (l <= i * y) break;
                }
            }
        }
    }
    for (int i = 0; i <= maxi; i++) swap(m1[i], m[i]);
}

bool check(int x) {
    for (int i = 0; i < a; i++) m[i] = -1;
    m[a] = b;
    for (int i = 0; i < l; i++) step(x);
    for (int i = 0; i <= a; i++) {
        if (m[i] != -1) return true;
    }
    return false;
}

int main() {
    cin >> a >> x >> b >> y >> l;
    maxi = a;
    int l = 0, r = (a * x + b * y) / ::l + 1;
    while (r > l + 1) {
        int m = (l + r) / 2;
        if (check(m)) l = m;
        else r = m;
    }
    cout << l;
    return 0;
}