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

Input: Consider Input: Sentence: 'a family out snow skiing on a blustery day'. Find frequency of the letter 'i'

Output: 3


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

Output: 1


Input: Consider Input: Sentence: 'a woman is holding a plate with a cake'. Find frequency of the letter 'i'


Output: 3