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

Input: Consider Input: Sentence: 'people waiting on a train platform in a wooded area'. Find frequency of the letter 'p'

Output: 3


Input: Consider Input: Sentence: 'a bunch of broken down trains sit in a yard'. Find frequency of the letter 'n'

Output: 5


Input: Consider Input: Sentence: 'two red vintage tour buses parked in a field'. Find frequency of the letter 'n'


Output: 2