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 group of people standing around an airplane on top of a field'. How many words start with the letter 'a' in the sentence.

Ex Output:
5


Ex Input:
Sentence: 'a colorful sculpture of an elephant in a park'. How many words start with the letter 'a' in the sentence.

Ex Output:
3


Ex Input:
Sentence: 'a red fire truck driving down a street next to a tall white building'. How many words start with the letter 't' in the sentence.

Ex Output:

3