A Japanese startup Kayac released mixi [J] application “Unko Enzan [J]” for educational purpose. This is an arithmetic learning application for the primary-school pupils. However, it has funny characteristic. Poos are featured on all problems. “Unko Enzan” means “Poo Arithmetic” in Japanese. Can you solve this problem? “If a coiled poo has a diameter of 16 cm, how many centimeters is the perimeter