import math
import sequtils
import strutils
import strformat

let trick_or_treat =  map(stdin.readLine().split(" "), proc(x: string): int = x.parseInt()) 
let trick = toBin(trick_or_treat[0], 10)
let treat = toBin(trick_or_treat[1], 10)

let answer: int = trick_or_treat[0] or trick_or_treat[1]
echo(fac(answer))