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

Input: Consider Input: Sentence: 'a closeup view of a bathroom sink, that is very modern'. Find frequency of the letter 'e'

Output: 4


Input: Consider Input: Sentence: 'an image of a cautionary construction sign'. Find frequency of the letter 'a'

Output: 5


Input: Consider Input: Sentence: 'a person feeding a cow with a bottle'. Find frequency of the letter 'd'


Output: 1