#include <bits/stdc++.h>
using namespace std;
#define rep(i, x, limit) for (long long i = (long long)x; i < (long long)limit; i++)
#define REP(i, x, limit) for (long long i = (long long)x; i <= (long long)limit; i++)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define el endl
#define spa " "
#define Yes cout << "Yes" << el
#define No cout << "No" << el
#define YES cout << "YES" << el
#define NO cout << "NO" << el
#define eps (1e-10)
#define Equals(a,b) (fabs((a) - (b)) < eps )
#define debug(x) cerr << #x << " = " << x << el
using ll = long long;
using ull = unsigned long long;
using pii = pair<int,int>;
using pll = pair<ll,ll>;
using vi = vector<int>;
using vl = vector<ll>;
using vvl = vector<vector<ll>>;
using vs = vector<string>;
using vb = vector<bool>;
const double pi = 3.141592653589793238;
const int inf = 1073741823;
const ll infl = 1LL << 60;
const string ABC = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
const string abc = "abcdefghijklmnopqrstuvwxyz";
const ll MOD = 998244353;
#include<atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using vm = vector<mint>;
ll base(ll a){
  return a+2*1e7+1;
}
bool ok(ll a){
  if(a>=0&&a<4*1e7+2)return true;
  return false;
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  ll t,x,a,y,b;cin>>t>>x>>a>>y>>b;
  vl D(4*1e7+2,infl);
  D[base(0)]=0;
  priority_queue<pll,vector<pll>,greater<pll>> pq;
  pq.push({0,base(0)});
  while(!pq.empty()){
    auto [val,ind]=pq.top();pq.pop();
    if(D[ind]<val)continue;
    if(ok(ind+1)){
      if(D[ind+1]>val+1){
        D[ind+1]=val+1;
        pq.push({val+1,ind+1});
      }
    }
    if(ok(ind+a)){
      if(D[ind+a]>val+x){
        D[ind+a]=val+x;
        pq.push({val+x,ind+a});
      }
    }
    if(ok(ind-b)){
      if(D[ind-b]>val+y){
        D[ind-b]=val+y;
        pq.push({val+y,ind-b});
      }
    }
  }
  cout<<D[base(t)]<<el;
}