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

Input: Consider Input: Sentence: 'a doll with huge eyes and black hair with blunt bangs holds a red umbrella'. Find frequency of the letter 'e'

Output: 5


Input: Consider Input: Sentence: 'several zebras  and a giraffe in an enclosure'. Find frequency of the letter 's'

Output: 3


Input: Consider Input: Sentence: 'a large brown pug down reaching up on a table'. Find frequency of the letter 'r'


Output: 3