In this task, you need to count the number of words in a sentence that contain the given letter

Ex Input:
Sentence: 'there is a person awaiting to cross this street'. How many words contain the letter 'a' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'a water fountain sitting in the middle of a bathroom'. How many words contain the letter 'h' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'children are getting off a bus while a woman directs them'. How many words contain the letter 'n' in the sentence.

Ex Output:

3