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

Input: Consider Input: Sentence: 'eight donuts are cooked together in oil in a metal tray'. Find frequency of the letter 'h'

Output: 2


Input: Consider Input: Sentence: 'a person riding a surfboard in the middle of a wave'. Find frequency of the letter 'o'

Output: 3


Input: Consider Input: Sentence: 'a man sitting near his truck with his surf board on the ground'. Find frequency of the letter 's'


Output: 4