$4\mathrm{.}16\mathrm{.}3$: Basic while loop expression.

Write a while loop that repeats while user$\_$num $1.$ In each loop iteration, divide user$\_$num by $2,$ then print user$\_$num.

Sample output with input: $20$

$10\mathrm{.}05\mathrm{.}02\mathrm{.}51\mathrm{.}250\mathrm{.}625$

Note: If the submitted code has an infinite loop, the system will stop running the code after a few seconds and report "Program end never reached." The system doesn't print the test case that caused the reported message.