text: There's a function called int. It means perform the  following division and drop the remainder. For example,\nint(3692/10)=369. Further, int(3692/10)*10=3690.\n"*" means times.\nThe rule is: to find the number following a number, let the\nfirst number be N, then the following one is\n\nint(N/10)*[N-int(N/10)*10]  for example,\nWhen N is 3692 then the rule translates to:\n......369*[3692-(369)*10]=\n......369*[3692-3690]=\n......369*2=738