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

Ex Input:
Sentence: 'a giraffe biting into a tree branch with great ferocity'. How many words contain the letter 'z' in the sentence.

Ex Output:
0


Ex Input:
Sentence: 'a group of people cooking pancakes in the field'. How many words contain the letter 'g' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'a short train is coming down the train tracks'. How many words contain the letter 'n' in the sentence.

Ex Output:

4