Input (grade 13): The name Keith was retired in the spring of 2001 and was replaced with Kirk, but the name Kirk has yet to be used, as the 2006 Atlantic hurricane season did not have enough storms to reach the name.
Output (grade 4): The name Keith was retired in the Spring of 2001. The name Kirk was put on the list in 2006, but Kirk was not used, so it must be used again in 2012.