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

Input: Consider Input: Sentence: 'there are trains that are on the train track'. How many words contain the letter 'z' in the sentence.

Output: 0


Input: Consider Input: Sentence: 'a cat sitting on the arm of a chair'. How many words contain the letter 'g' in the sentence.

Output: 1


Input: Consider Input: Sentence: 'a group of cross country skiers take off for a trek'. How many words contain the letter 'a' in the sentence.


Output: 3