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

Input: Consider Input: Sentence: 'a man in costume talking on a cell phone'. Find frequency of the letter 'm'

Output: 2


Input: Consider Input: Sentence: 'oranges are sitting in a bowl on a table'. Find frequency of the letter 'a'

Output: 5


Input: Consider Input: Sentence: 'black leather sofa in a room with white walls'. Find frequency of the letter 'i'


Output: 3