#include <bits/stdc++.h>
// clang-format off
using namespace std; using ll=long long; using ull=unsigned long long; using pll=pair<ll,ll>; const ll INF=4e18;
void print0(){}; template<typename H,typename... T> void print0(H h,T... t){cout<<h;print0(t...);}
void print(){print0("\n");}; template<typename H,typename... T>void print(H h,T... t){print0(h);if(sizeof...(T)>0)print0(" ");print(t...);}
void perr0(){}; template<typename H,typename... T> void perr0(H h,T... t){cerr<<h;perr0(t...);}
void perr(){perr0("\n");}; template<typename H,typename... T>void perr(H h,T... t){perr0(h);if(sizeof...(T)>0)perr0(" ");perr(t...);}
void ioinit() { cout<<fixed<<setprecision(15); cerr<<fixed<<setprecision(6); ios_base::sync_with_stdio(0); cin.tie(0); }
#define debug1(a) { cerr<<#a<<":"<<a<<endl; }
#define debug2(a,b) { cerr<<#a<<":"<<a<<" "<<#b<<":"<<b<<endl; }
#define debug3(a,b,c) { cerr<<#a<<":"<<a<<" "<<#b<<":"<<b<<" "<<#c<<":"<<c<<endl; }
#define debug4(a,b,c,d) { cerr<<#a<<":"<<a<<" "<<#b<<":"<<b<<" "<<#c<<":"<<c<<" "<<#d<<":"<<d<<endl; }
// clang-format on
int main() {
    ioinit();

    ll T, X, A, Y, B;
    cin >> T >> X >> A >> Y >> B;
    ll ans = INF;
    if (T == 0) {
        ans = 0;
    }
    if (T < 0) {
        {
            ll mv = ((abs(T) + B - 1) / B);
            ll pt = -B * mv;
            ll t = Y * mv;
            ll diff = (T - pt);
            ans = min(ans, t + diff);

            ll mva = diff / A;
            ll pta = pt + A * mva;
            ll ta = t + X * mva;
            ll diffa = T - pta;
            ans = min(ans, ta + diffa);
        }
    }
    if (T > 0) {
        {
            ans = min(ans, T);
        }
        {
            ll mv = T / A;
            ll pt = A * mv;
            ll t = X * mv;
            ll diff = T - pt;
            ans = min(ans, t + diff);
        }
        {
            ll mva = (1 + T / A);
            ll pt = A * mva;
            ll t = X * mva;
            ll diff = pt - T;

            ll mvb = ((diff + B - 1) / B);
            ll ptb = pt - B * mvb;
            ll tb = t + Y * mvb;

            ll diffb = T - ptb;

            ans = min(ans, tb + diffb);
        }
    }
    print(ans);
    return 0;
}