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: 'an orange and white scooter carrying two passengers drives down a wet street while the passenger of the scooter holds a purple umbrella'. How many words start with the letter 'a' in the sentence.

Ex Output:
4


Ex Input:
Sentence: 'decorative objects on a counter in front of a framed picture'. How many words start with the letter 'o' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'a silver frosted cupcake with human figure decoration on it'. How many words start with the letter 's' in the sentence.

Ex Output:

1