import java.util.Scanner;

public class Bounce {
    public static final Scanner SC = new Scanner(System.in);

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String[] input = sc.nextLine().split(" ");
        int n = Integer.parseInt(input[0]);
        int m = Integer.parseInt(input[1]);
        long[][] matrix = new long[n][m];
        long sum = 0;
        for (int row = 0; row < n; row++) {
            for (int col = 0; col < m; col++) {
                matrix[row][col] = (long) Math.pow(2,row + col);
            }
        }
        for (int currentRow = 0; currentRow < n ; currentRow++) {
            if (currentRow % 2 == 0){

                for (int currentCol = 0; currentCol < m - 1; currentCol += 2) {
                    if (currentRow != 0 && currentRow != n - 1){
                        sum+= matrix[currentRow][currentCol];
                    }
                    sum += matrix[currentRow][currentCol];
                }
            }else {

                for (int currentCol = 1; currentCol < m; currentCol += 2) {
                    if (currentCol != 0 && currentCol != m - 1){
                        sum+= matrix[currentRow][currentCol];
                    }
                    sum += matrix[currentRow][currentCol];
                }
            }
        }
        System.out.println(sum);
    }
}