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

Input: Consider Input: Sentence: 'a dilapidated bench in a park under a tree'. Find frequency of the letter 'p'

Output: 2

Input: Consider Input: Sentence: 'a black cat laying down on a bed'. Find frequency of the letter 'y'

Output: 1

Input: Consider Input: Sentence: 'a large cooked pizza on a dining table'. Find frequency of the letter 'n'
Output: 3