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

Input: Consider Input: Sentence: 'a closeup view of a bathroom sink, that is very modern'. Find frequency of the letter 'e'

Output: 4


Input: Consider Input: Sentence: 'a herd of giraffes in tall african grass'. Find frequency of the letter 'a'

Output: 6


Input: Consider Input: Sentence: 'a white stove top oven sitting inside of a kitchen'. Find frequency of the letter 'i'


Output: 6