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

Input: Consider Input: Sentence: 'a few men walking through a market place'. Find frequency of the letter 'f'

Output: 1


Input: Consider Input: Sentence: 'two people are riding on canoes down a river'. Find frequency of the letter 'e'

Output: 5


Input: Consider Input: Sentence: 'a sign says "do not enter busses only" next to a bus'. Find frequency of the letter 'd'


Output: 1