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

Input: Consider Input: Sentence: 'a  woman standing next to a man on a motorcycle in front of a market'. Find frequency of the letter 'l'

Output: 1


Input: Consider Input: Sentence: 'a jet that is flying in the sky with a banner behind it'. Find frequency of the letter 'r'

Output: 1


Input: Consider Input: Sentence: 'a cat that is sitting on top of a keyboard'. Find frequency of the letter 'i'


Output: 3