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

Ex Input:
Sentence: 'a man in a restaurant makes the v sign with both hands'. How many words contain the letter 'n' in the sentence.

Ex Output:
5


Ex Input:
Sentence: 'a mother and son holding wii controls in front of a christmas fireplace'. How many words contain the letter 'x' in the sentence.

Ex Output:
0


Ex Input:
Sentence: 'some giraffe are standing in the middle of a green pasture'. How many words contain the letter 's' in the sentence.

Ex Output:

3