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

Ex Input:
Sentence: 'a stop sign casting a shadow of a sign that says war'. How many words contain the letter 'y' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'some elephants in a field of grass near a tree'. How many words contain the letter 'k' in the sentence.

Ex Output:
0


Ex Input:
Sentence: 'a bedroom complete with a bed dresser and ceiling fan'. How many words contain the letter 'm' in the sentence.

Ex Output:

2