In this task, you need to count the number of words in a sentence that start with the given letter. Answer with numbers and not words.

Input: Consider Input: Sentence: 'a colorful sculpture of an elephant in a park'. How many words start with the letter 'a' in the sentence.

Output: 3


Input: Consider Input: Sentence: 'a green fire hydrant is in the middle of an open dirt hole in a construction area'. How many words start with the letter 'a' in the sentence.

Output: 4


Input: Consider Input: Sentence: 'a stop sign mounted on a pole with a street sign with a forest in the background'. How many words start with the letter 'a' in the sentence.


Output: 4