$(13\%)$ Write a function void under $($int s$)$ that prints an "underwear" of size s$.$ You

can assume that $s$ is even and $s4.$ There shall be s rows of printings. The top and bottom

rows shall have $2$ s and $s\text{'}**\text{'}$ symbols respectively. The following shows some example

printing outputs for various function calls. $($You may use to denote a space in your answer

for clarity.$)$