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

Ex Input:
Sentence: 'a person in the air with a skateboard upside down underneath'. How many words contain the letter 'i' in the sentence.

Ex Output:
4


Ex Input:
Sentence: 'a man flying through the air while riding a snowboard'. How many words contain the letter 'x' in the sentence.

Ex Output:
0


Ex Input:
Sentence: 'a surfer is riding a small wave in the ocean'. How many words contain the letter 'a' in the sentence.

Ex Output:

5