Goal: Learn to write do$-$while loops.

Assignment: Given the following sequence of operations: starting from a number U$0,$ divide it by $2$ if it is even, or multiply it by $3$ and add $1$ if it is odd. Collatz's conjecture states that this sequence will always converge to $1,$ no matter the starting number.

Assume a Scanner stdin has already been declared and instantiated. int variable un will be input by the user and serve as a starting point, and int variable counter will serve to track the progress in the sequence. Write a do$-$while loop that implements this sequence of operations until Un reaches $1.$ Print out the values of Un during the whole process.

Sample output $($user input enclosed in $<>)$:

$<7>$

u$0=7$

u$1=22$

u$2=11$

u$3=34$

u$4=17$

u$5=52$

u$6=26$

u$7=13$

u$8=40$

u$9=20$

u$10=10$

u$11=5$

u$12=16$

u$13=8$

u$14=4$

u$15=2$

u$16=1$