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 soccer player running and kicking a soccer ball during a match'. How many words start with the letter 'a' in the sentence.

Ex Output:
4


Ex Input:
Sentence: 'three hotdogs on a picnic table with soft drinks'. How many words start with the letter 'w' in the sentence.

Ex Output:
1


Ex Input:
Sentence: 'a couple of trains parked next to each other'. How many words start with the letter 'n' in the sentence.

Ex Output:

1