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

Ex Input:
Sentence: 'a blue bowl holding mashed bananas and oatmeal with a bottle of sugar and cinnamon sitting beside it'. Find frequency of the letter 'g'

Ex Output:
3


Ex Input:
Sentence: 'a girl laying on a bed posing for a picture'. Find frequency of the letter 'i'

Ex Output:
4


Ex Input:
Sentence: 'an oven fired pizza with ricotta cheese and other toppings'. Find frequency of the letter 'h'

Ex Output:

3