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

Input: Consider Input: Sentence: 'two people wearing snowboards sitting on a snowy slope'. Find frequency of the letter 's'

Output: 5


Input: Consider Input: Sentence: 'a gray colored pigeon that is perched on a railing outside of a building, with other buildings in the background'. Find frequency of the letter 'e'

Output: 7


Input: Consider Input: Sentence: 'a woman sitting at a desk in front of three kids'. Find frequency of the letter 'h'


Output: 1