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 man wearing a straw hat and a black shirt'. How many words start with the letter 'a' in the sentence.

Ex Output:
4


Ex Input:
Sentence: 'group of zebras and gazelles grazing on the grass'. How many words start with the letter 'g' in the sentence.

Ex Output:
4


Ex Input:
Sentence: 'dog playing frisbee on the beach with ocean in background'. How many words start with the letter 'o' in the sentence.

Ex Output:

2