function factorial(n) {
    if (n <= 1) {
        return 1;
    } else {
        return n * factorial(n - 1);
    }
}
function Main(input) {
    const src = input.replace("\n", "").split(" ");
    const a = parseInt(src[0]);
    const b = parseInt(src[1]);
    const c = a | b;
    console.log(factorial(c));
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));