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 busy train yard packed with trains and tracks'. How many words start with the letter 't' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'a photo of a waterway with several boats along the shore'. How many words start with the letter 'w' in the sentence.

Ex Output:
2


Ex Input:
Sentence: 'a couple of sheep are relaxing in a field'. How many words start with the letter 'a' in the sentence.

Ex Output:

3