In this task, you need to count the number of times the given letter appears in the given sentence.

Input: Consider Input: Sentence: 'a truck with a camper sits parked in some vegetation'. Find frequency of the letter 's'

Output: 3


Input: Consider Input: Sentence: 'a piece of meat covered in ketchup next to a hamburger on a green plate'. Find frequency of the letter 'g'

Output: 2


Input: Consider Input: Sentence: 'a large elephants reflection in a cars side view mirror, with other elephants in the distance'. Find frequency of the letter 'i'


Output: 8