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 person on a court with a tennis racket'. How many words start with the letter 'p' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a group of young people riding snow boards down a snow covered hillside'. How many words start with the letter 'a' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'three hot dogs are stuffed in buns are ready to serve'. How many words start with the letter 'd' in the sentence.

Ex Output:

1