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

Input: Consider Input: Sentence: 'a large motorcycle that has a man dressed in old clothing next to it'. Find frequency of the letter 'a'

Output: 6


Input: Consider Input: Sentence: 'a bird is perched on a container in a person's hand'. Find frequency of the letter 'c'

Output: 2


Input: Consider Input: Sentence: 'a pair of men standing on snowboards giving the thumbs up'. Find frequency of the letter 'a'


Output: 4