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

Input: Consider Input: Sentence: 'a cat sleeping near lots of pairs of shoes'. Find frequency of the letter 'r'

Output: 2


Input: Consider Input: Sentence: 'slices of orange are arranged on a plate'. Find frequency of the letter 's'

Output: 2


Input: Consider Input: Sentence: 'a train traveling a trussle over a river'. Find frequency of the letter 'g'


Output: 1