import java.util.*;
public class Main{
	public void process(){
		Scanner sc = new Scanner(System.in);
		String pen;
		String box;
		String price;

		String[] penStArr;
		String[] boxStArr;
		String[] priceStArr;

		int colorPen;
		int whitePen;
		int colorA;
		int whiteB;
		int whiteC;
		int colorD;
		int x;
		int y;
		int z;
		
		int sum1;
		int sum2;
		int sum3;

		while(sc.hasNext()){
			pen = sc.nextLine();
			box = sc.nextLine();
			price = sc.nextLine();

			colorPen = Integer.parseInt(pen.split(" ")[0]);
			whitePen = Integer.parseInt(pen.split(" ")[1]);

			colorA = Integer.parseInt(box.split(" ")[0]);
			whiteB = Integer.parseInt(box.split(" ")[1]);
			whiteC = Integer.parseInt(box.split(" ")[2]);
			colorD = Integer.parseInt(box.split(" ")[3]);

			x = Integer.parseInt(price.split(" ")[0]);
			y = Integer.parseInt(price.split(" ")[1]);
			z = Integer.parseInt(price.split(" ")[2]);

			int bound1 = colorPen/colorD;
			int bound2 = whitePen/whiteC;
			int bound3 = (colorPen/colorA > whitePen/whiteB)? whitePen/whiteB : colorPen/colorA;

			int finalSum = 0;
			int tempSum = 0;
			for(int i = 0; i<= bound1; i++){
				for(int j = 0; j<= bound2; j++){
					for(int m = 0; m<= bound3; m++){
						if((i*colorD + m*colorA) > colorPen || (j*whiteC+m*whiteB) > whitePen){
							break;
						}
						tempSum = i*z + j*y + m*x;
						finalSum = tempSum > finalSum ? tempSum : finalSum;
					}
				}
			}
			System.out.println(finalSum);

		}
	}

	
	public static void main(String[] args){
		Main m = new Main();
		m.process();
	}
}