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 man serving himself pizza in a wooden booth'. Find frequency of the letter 'n'

Output: 4


Input: Consider Input: Sentence: 'a horse is pulling a cart with barrels of beer on it'. Find frequency of the letter 'b'


Output: 2