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 with a skateboard that is in the street'. Find frequency of the letter 'o'

Output: 1


Input: Consider Input: Sentence: 'this marketplace has a lot of fresh fruit and vegetables'. Find frequency of the letter 'v'

Output: 1


Input: Consider Input: Sentence: 'a large group of people on a sidewalk'. Find frequency of the letter 'e'


Output: 4