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

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

Ex Output:
6


Ex Input:
Sentence: 'a bowl of vegetables in a soup like substance next to a spoon'. Find frequency of the letter 'a'

Ex Output:
5


Ex Input:
Sentence: 'a work space with wood floors and a window'. Find frequency of the letter 'e'

Ex Output:

1