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: 'several people are playing frisbee in a park'. How many words start with the letter 'a' in the sentence.

Output: 2


Input: Consider Input: Sentence: 'a woman sitting in a chair next to a lot of vases'. How many words start with the letter 'a' in the sentence.

Output: 3


Input: Consider Input: Sentence: 'three boys run on a green field one throwing a frisbee'. How many words start with the letter 'f' in the sentence.


Output: 2