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

Input: Consider Input: Sentence: 'some food on plates next to each other on a table'. Find frequency of the letter 'e'

Output: 6


Input: Consider Input: Sentence: 'a couple of boys in a field playing baseball'. Find frequency of the letter 'i'

Output: 3


Input: Consider Input: Sentence: 'a woman hitting a ball with the tennis racket at the tennis court'. Find frequency of the letter 's'


Output: 2