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

using ll = long long;

#define TYPE_OF( VAR ) remove_const<remove_reference<decltype( VAR )>::type >::type
#define UNTIE ios_base::sync_with_stdio( false ); cin.tie( nullptr ) 
#define CIN( LL , A ) LL A; cin >> A 
#define ASSERT( A , MIN , MAX ) assert( MIN <= A && A <= MAX ) 
#define CIN_ASSERT( A , MIN , MAX ) CIN( TYPE_OF( MAX ) , A ); ASSERT( A , MIN , MAX ) 
#define FOREQ( VAR , INITIAL , FINAL ) for( TYPE_OF( FINAL ) VAR = INITIAL ; VAR <= FINAL ; VAR ++ )  
#define QUIT return 0 
#define RETURN( ANSWER ) cout << ( ANSWER ) << "\n"; QUIT 

int main()
{
  UNTIE;
  constexpr const ll bound = 10000000;
  CIN_ASSERT( T , - bound , bound );
  assert( T != 0 );
  CIN_ASSERT( X , 1 , bound );
  CIN_ASSERT( A , X , bound );
  CIN_ASSERT( Y , 1 , bound );
  CIN_ASSERT( B , 1 , bound );
  ll y_lb = ( T >= 0 ? 0 : ( - T + B - 1 ) / B );
  ll t_min = y_lb * B + ( T + y_lb * Y );
  ll y_ub = t_min / B;
  ll t;
  FOREQ( y , y_lb , y_ub ){
    t = T + y * B;
    t = y * Y + ( t / A ) * X + ( t % A );
    if( t_min > t ){
      t_min = t;
    }
  }
  RETURN( t_min );
}