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

Input: Consider Input: Sentence: 'a view from a bathroom shows an open door'. Find frequency of the letter 'o'

Output: 7


Input: Consider Input: Sentence: 'children with scissors and construction paper in a school classroom'. Find frequency of the letter 'c'

Output: 6


Input: Consider Input: Sentence: 'a couple of men sitting next to each other under an umbrella'. Find frequency of the letter 'n'


Output: 5