#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    ll T, X, A, Y, B;
    cin >> T;
    cin >> X >> A;
    cin >> Y >> B;

    ll g = gcd(A, B);
    const ll INF = (1LL << 62);
    ll ans = INF;

    if (T > 0) {
        ll lim = A / g;
        for (ll p = 0; p < lim; p++) {
            ll f = (T + B * p) / A;
            ll cost = T + (Y + B) * p - (A - X) * f;
            ans = min(ans, cost);
        }
    } else {
        ll lim = B / g;
        for (ll f = 0; f < lim; f++) {
            ll need = A * f - T;          // T < 0 なので need > 0
            ll p = (need + B - 1) / B;    // ceil(need / B)
            ll cost = T + (X - A) * f + (Y + B) * p;
            ans = min(ans, cost);
        }
    }

    cout << ans << '\n';
    return 0;
}