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.

Ex Input:
Sentence: 'a man with a tennis rack on a court'. How many words start with the letter 'a' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'a young kid in a hat with a parrot on his shoulder'. How many words start with the letter 'a' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'a man is dong a trick on a skateboard'. How many words start with the letter 'a' in the sentence.

Ex Output:

3