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

Input: Consider Input: Sentence: 'a truck with a camper sits parked in some vegetation'. Find frequency of the letter 's'

Output: 3


Input: Consider Input: Sentence: 'a man flying through the air on top of a skateboard'. Find frequency of the letter 'h'

Output: 3


Input: Consider Input: Sentence: 'a man standing next to a laptop and bottles of beer'. Find frequency of the letter 'o'


Output: 4