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

Input: Consider Input: Sentence: 'three birds perched on top of a wire fence'. How many words contain the letter 'b' in the sentence.

Output: 1


Input: Consider Input: Sentence: 'trash cans and a fire hydrant are on the curb of a sidewalk'. How many words contain the letter 'u' in the sentence.

Output: 1


Input: Consider Input: Sentence: 'a runner eating several doughnuts stacked like a sandwich'. How many words contain the letter 'a' in the sentence.


Output: 6