import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int m = scanner.nextInt();
        long sum = 0;

        long[][] matrix = new long[n][m];

        matrix[0][0] = 1;
        for (int i = 0; i < m - 1; i++) {
            matrix[0][i + 1] = matrix[0][i] + 3;
        }

        for (int i = 0; i < n - 1; i++) {
            for (int j = 0; j < m; j++) {
                matrix[i + 1][j] = matrix[i][j] + 3;
            }
        }
        for (int i = 0; i < n; i++) {
            for (int j = 0; j < m; j += 2) {
                if (i % 2 == 0) {
                    sum += matrix[i][j];
                }
            }
        }
        for (int i = 0; i < n; i++) {
            for (int j = 1; j <= m; j += 2) {
                if (i % 2 != 0) {
                    sum += matrix[i][j];
                }
            }
        }
        for (int i = 1; i < n - 1; i++) {
            for (int j = 1; j < m - 1; j+=2) {
                if (i % 2 != 0) {
                    sum += matrix[i][j];
                }
            }
        }
        for (int i = 1; i < n - 1; i++) {
            for (int j = 2; j < m - 1; j+=2) {
                if (i % 2 == 0) {
                    sum += matrix[i][j];
                }
            }
        }
        System.out.println(sum);
    }
}