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

Input: Consider Input: Sentence: 'girls posing of a picture one holding a tennis racket the other wearing a crown'. Find frequency of the letter 'g'

Output: 4


Input: Consider Input: Sentence: 'a construction sign is displayed on a street'. Find frequency of the letter 'i'

Output: 4


Input: Consider Input: Sentence: 'a hello kitty a mouse and a bear stuffed animals'. Find frequency of the letter 'b'


Output: 1