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

Input: Consider Input: Sentence: 'this is an image of a woman playing tennis'. Find frequency of the letter 'f'

Output: 1


Input: Consider Input: Sentence: 'a white police vehicle parked on a paved street'. Find frequency of the letter 'a'

Output: 4


Input: Consider Input: Sentence: 'a woman stands in front of an open laptop'. Find frequency of the letter 'p'


Output: 3