import java.math.BigDecimal; import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner scan = new Scanner(System.in); int A = scan.nextInt(); int B = scan.nextInt(); scan.close(); // double d = 0.8 + 0.2 * (double)B; // int ans = 50 * A + (int) (50 * A / d); // BigDecimal bdA = new BigDecimal(A); // BigDecimal bdB = new BigDecimal(B); BigDecimal bd = new BigDecimal(0.8); bd = bd.add(new BigDecimal((double) 0.2 * (double)B)); BigDecimal a1 = new BigDecimal(50 * A); BigDecimal bd2, a2; bd2 = a1.divide(bd, 5, BigDecimal.ROUND_HALF_UP); a2 = bd2.setScale(1, BigDecimal.ROUND_DOWN); int a = a2.intValue(); System.out.println(a + 50 * A); } }