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

Input: Consider Input: Sentence: 'a bird in a tree looking up at branches'. Find frequency of the letter 'e'

Output: 3


Input: Consider Input: Sentence: 'a man playing baseball on a television set'. Find frequency of the letter 'l'

Output: 4


Input: Consider Input: Sentence: 'there is a black hat and white glove with birthday greetings'. Find frequency of the letter 'v'


Output: 1