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 green place mat sitting on a table with a couple of plates of food and a drink placed upon it'. How many words start with the letter 'p' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'a couple of people that are playing wii'. How many words start with the letter 'p' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'a little boy standing under a red stop sign'. How many words start with the letter 'b' in the sentence.

Ex Output:

1