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

Ex Input:
Sentence: 'an elephant near a man sitting down'. How many words contain the letter 'y' in the sentence.

Ex Output:
0


Ex Input:
Sentence: 'an elephant that is eating some leaves from a tree'. How many words contain the letter 'n' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'four stuffed teddy bears that are unusually skinny'. How many words contain the letter 'n' in the sentence.

Ex Output:

2