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 large jet liner sitting on top of an airport runway'. How many words start with the letter 'a' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'many sheep gather on a truck and in a field eating hay'. How many words start with the letter 'h' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a bus next to a bus stop sign waiting for passengers'. How many words start with the letter 'b' in the sentence.

Ex Output:

2