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

Input: Consider Input: Sentence: 'a woman in a messy kitchen with a child'. Find frequency of the letter 'a'

Output: 4


Input: Consider Input: Sentence: 'a woman walking on a shore next to a river'. Find frequency of the letter 'v'

Output: 1


Input: Consider Input: Sentence: 'a statue of a man holding an umbrella is pictured'. Find frequency of the letter 'f'


Output: 1