import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import static java.lang.System.in; public class No445 { public static void main(String[] args) throws IOException { BufferedReader reader = new BufferedReader(new InputStreamReader(in)); String[] inputs = reader.readLine().split(" "); int A = Integer.parseInt(inputs[0]); int B = Integer.parseInt(inputs[1]); int answer = 50 * A + (int) Math.floor((50 * A) / (0.8 + 0.2 * B)); System.out.println(answer); } }