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

Ex Input:
Sentence: 'a plate with a grilled sanwich next to a bowl of tomato soup'. How many words contain the letter 'a' in the sentence.

Ex Output:
6


Ex Input:
Sentence: 'a man and a woman stand under an umbrella'. How many words contain the letter 's' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'the tennis player has stepped on the court'. How many words contain the letter 's' in the sentence.

Ex Output:

3