ll h,w,a,b,c,d;

ll f(ll y){
	ll x;
	if(y||c){
		ll yb=min(y*b,w);
		ll g=h*w-y*d;
		x=g/+(yb*a+c);
		if(x*a>h){
			x=h/+a;
			ll e=(g-x*c)-yb*h;
			if(e>0){
				if(c){
					x+=e/+c;
				}else{
					x=h+w;
				}
			}
		}else{
			x>?=0;
		}
	}else{
		x=h+w;
	}
	return x+y;
}

{
	rd(h,w,a,b,c,d);
	ll y=tsearch_argmin[ll,y,0,h+w](f(y));
	ll z=min[y,y,y+9](f(y));
	wt(z);
}