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

Ex Input:
Sentence: 'there are some warning signs on a public toilet'. How many words contain the letter 'a' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'a rack full of clothes in a small bedroom'. How many words contain the letter 'o' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'the surfers are waiting in line the surf the small waves in the water'. How many words contain the letter 'q' in the sentence.

Ex Output:

0