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

Input: Consider Input: Sentence: 'a group of people standing around a table filled with assorted electronic devices'. Find frequency of the letter 'w'

Output: 1


Input: Consider Input: Sentence: 'person wearing all white leaned up against a wall with a yellow sign'. Find frequency of the letter 'a'

Output: 8


Input: Consider Input: Sentence: 'this is a desk with a computer on it'. Find frequency of the letter 's'


Output: 3