#include <iostream>
#include <string>
#include <vector>

using std::cin;
using std::cout;

int main() {
    size_t rows;
    size_t columns;
    cin >> rows >> columns;
    std::vector<std::vector<size_t>> matrix(
        rows,
        std::vector<size_t>(columns));
    for (size_t i = 0; i != rows; ++i) {
        for (size_t j = 0; j != columns; ++j) {
            if (i == 0 && j == 0) {
                matrix[i][j] = 1;
            } else {
                if (i >= 2 && j >= 1) {
                    matrix[i][j] += matrix[i - 2][j - 1];
                }
                if (i >= 1 && j >= 2) {
                    matrix[i][j] += matrix[i - 1][j - 2];
                }
            }
        }
    }
    cout << matrix[rows - 1][columns - 1] << std::endl;
}