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

Ex Input:
Sentence: 'black and white photograph of a man using a cell phone on the street'. How many words contain the letter 'r' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'some stop lights that are at an intersection'. How many words contain the letter 'c' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a view of a city street with oncoming traffic taken through metal posts of a sign'. How many words contain the letter 'i' in the sentence.

Ex Output:

6