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

Input: Consider Input: Sentence: 'a number of small boats on a beach near an umbrella'. Find frequency of the letter 's'

Output: 2


Input: Consider Input: Sentence: 'a woman swinging a tennis racquet towards a tennis ball'. Find frequency of the letter 'e'

Output: 3


Input: Consider Input: Sentence: 'a close up of a person typing on a laptop'. Find frequency of the letter 'a'


Output: 4