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

Ex Input:
Sentence: 'man in a radio studio wearing a suit in front of a microphone'. Find frequency of the letter 't'

Ex Output:
3


Ex Input:
Sentence: 'a young girl is brushing her teeth in this dated photo'. Find frequency of the letter 't'

Ex Output:
5


Ex Input:
Sentence: 'cat laying on the floor near some books'. Find frequency of the letter 'c'

Ex Output:

1