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

Ex Input:
Sentence: 'a jet airliner carrying a small shuttle above it'. How many words contain the letter 'r' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'a couple of horses standing next to each other on a field'. How many words contain the letter 'q' in the sentence.

Ex Output:
0


Ex Input:
Sentence: 'two cows on a hill with a mountain background'. How many words contain the letter 'a' in the sentence.

Ex Output:

4