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

Input: Consider Input: Sentence: 'an empty clean kitchen with island, marble countertops , stove and cabinetry'. Find frequency of the letter 'l'

Output: 3


Input: Consider Input: Sentence: 'a woman is playing an interactive video game'. Find frequency of the letter 't'

Output: 2


Input: Consider Input: Sentence: 'the elephant trunk of an elephant hanging over a guardrail'. Find frequency of the letter 'e'


Output: 6